Is pursuing Artistic Reputation worth it?

Just a quick correction here:

you get reputation for every season spent, not every piece made; otherwise any building artist would never become popular.

Now as mentioned by John, Benefactors are the better option, but there is a bit more to it to make it easier
Every time you get a Benefactor you get +3 xp; doing this takes a season, during this season you can host a feast or event to attract said benefactor so +1xp
so obviously you want to be finding as many benefactors as you can, so you want a high turn over of art, so taking Prolific Artist and being a poet is the way to go (Poets use Communication+Ability, doubles up for finding sponsors, takes little resources, and very little time); work out how many pieces you can crank out in a season and hunt down the appropriate amount of benefactors; you could argue that finding a benefactor or holding a "poetry reading" event does count as being diligent in your art from.

Now the trick to being a famous artist is actually being Bad at art; well to begin with. if you take Artistic reputation twice you need to create art of quality 12 or higher; which you can do with no ability (Communication 5 +5, Inspirational and Free Expression +6, Artes Liberalus 3 +1 = 12); further more you can further bonuses from improving your workshop as per Cities and Guilds, potentially up to +6. Being a Poet is a craft after all. Now this allows you to get the nice bonus reputation from rapidly rising in skill.

So you've got a high Communication, good social skills to wrangle benefactors, and Inspirational; So Agents, you can have a lot of them, dealing with people is basically your full time job already, and the moment they have a smidgen of loyalty to you they become near fanatics (loyalty being a personality trait after all). Now you can either have your Agents support your Poetry printer....I mean artistic talents, find new benefactors for you, eliminate competition, hype up your work; or your agents can be a series of benefactors who you just cycle out every year or so.

As with most art, presenting it while in a Magical Aura will help; as described on Pg 7 of Realms of Power: Magic, Magical Auras make things more vivid, clearer, superior. now mechanically this might not have an effect unless the aura is aligned to artistic talents, but its is far better then the drab Divine, distracting Faerie or demonic Infernal; plus if your art starts to produce Vis, you can get a whole bunch of new benefactors from strange, somewhat disturbing men or Magi as they like to be known.

Ah, reading fail on my part.

Starting really low on Ability score has the advantage of turning out art (and thus cycling benefactors) faster. Ideally the artist will only increase his AQ to the point where it's necessary to gain reputation from his art...but that jumps by 3 points per Reputation, which will be rough if you're just scraping by on the required AQ. It will be quite likely that you spend several seasons making art while gaining no reputation if you plan it wrong.

If you keep AQ just below 20 you're good until Reputation 6, when you need to improve your Craft Ability to hit 7, then 8. That said, if your AQ stays at 19, once you hit Rep6 you have to improve your Craft by 5 levels to get to Rep8, barring other improvements. Once you're in AQ21+, seeking out Benefactors is probably too time consuming in terms of completing artworks to cycle in a new benefactor.

well as a poet with the Prolific Artist you can crank out quality up to 40 and only take the base amount of time, considering you only need a quality of 30 to have a reputation of 10 you are never going to take more then a season to complete a piece of work
now getting to quality 30 is not as hard as it seems

Communication +3
Free expression +3
Inspirational +3
Natural Poet +3
Major Muse +3
Workshop Material Bonus +3
Workshop Innovation Bonus +3
Artes Liberales 6+specialty +3
Profession [Poet] 5+Specialty +6
= 30
Time taken 6 weeks

By stretching the system even further we can work out the cost of each AQ 30 poem
If they make 2 of these a season, and only work the minimum needed for their wealth level, the poet is making 309 labour points a year (after maintenance [36+15]), very quickly they are going to be wealthy of their level, this means that each poem is worth a bit more then 4 lots of their wealth level; by reputation 10 they should be greater or legendary level of income; this results in the cost of a single poem being about 271 pounds for greater or 1076 pounds for legendary. arguably the City and Guilds does say that this is not the best system for converting work into coin, and I may be doing some of the math wrong.

Hang on, you can only make 2 short poems a season according to "Time Spent Creating". That means 1 short poem takes a whole season at AQ 11-20.

I should have put the word virtue after Prolific Artist

Even without this virtue you could take assistants though this is far less effective; assuming effective leadership of 6 (which is high but not impossible), this means 6 assistants, each assistant reduces the normal time by 3.5 days, every two assistants is therefore a week off the normal production time.
Side note: 4 seasons a year = 12 months therefore 1 season = 3 Months. 1 Month = 4 weeks (easiest for math). 2 Poems = 1 Season therefore 1 Poem = Half a Season = 6 weeks.
Shortest amount of time an art piece can be constructed is 1/4 the normal length of time (pg125, 3rd paragraph) so about a fortnight (2 weeks).
The shortest amount of time an art piece's construction time can be reduced by assistance is 1/2 the normal length of time (pg125, 2rd paragraph) so about 3 weeks.
6 assistants reduces the normal amount of time to 3 weeks which means that at AQ 11-20 you are taking the normal amount of time thanks to assistants.
8 assistants reduces the normal time to 2 weeks (which is below the minimum) thus is too many for Poetry, effigy plates, songs or brooches.
The difference between a third and a quarter reduction becomes slightly important above AQ21 and higher as this will increase the times to 9 and 6 weeks respectfully; at 9 weeks you will not be able to complete a second art piece by the end of the season.

For larger projects the Prolific Artist virtue becomes even better; the base time of a year becomes a season; the base time of a decade becomes 2.5 years, a significant saving in time; to get to the 5 year mark with assistants would mean you need an effective leadership (mostly though agents maybe) of 60 (at the decade level assistants reduce by a month a piece).
Finally as an added bonus, the virtue is a supernatural virtue and thus aligns your character with a realm, allowing easier longevity rituals.

That requires a Supernatural Ability, not a Supernatural Virtue. Not every virtue provides an Ability.

Though if you really want to optimize you should be working on artistic reputation while focusing on faerie, where you can add virtues and flaws to various faerie entities based on your ability as an artist, doubling (at least!) the effectiveness of your character. If you wind up with a faerie sympathy to help boost your AQ levels...

I really don't see a need for Faerie Sympathy to improve AQ. AQ generally isn't the limiting factor, and as the thread has shown, having too much AQ above what you need to gain reputation actually slows you down.

No, but it is easier to get the AQ up if you start from low levels using a combination of ability and sympathy. In fact sympathy can justify a higher starting reputation with little ability (presumably at a young age) allowing you to gain more reputation by advancing your ability...
it also will tend to direct your eventual realm alignment towards faerie and avoid the risk of being infernal...

also you may note earlier it doesn't actually slow you down since the reputation is gained per season, not per work.

No, it does slow you down - because the longer you take per piece means the fewer benefactors you cycle through. It's +3 rep per benefactor (1 season finding one), but only +1 rep per season working.

Still the rest stands, in that you can generate an AQ with lower ability and thus gain more reputation from raising your ability (especially if you study under teachers with a good reputation score, which can be better than benefactors, as you gain reputation XP equal to their reputation... and they gain 1 xp in reputation for becoming your patron...