First, about the idea that putting points into abilities is a vote regarding what stories you want your character involved in. I didn’t give my companion a score of 5 in Single Weapon because I wanted lots of fighting, I gave him a score of 5 in Single Weapon because when fighting occurs, I didn’t want to be helpless. My experience is that GMs don’t only give you adventures where you are good at things, they give you adventures where entertaining things happen, and doing things you are not very good at is often entertaining.
Second, regarding the relative value of Languages and Single Weapon Skill; my Verditius mage is much more interested in learning Occitan than Single Weapon. He wants to build a stained glass window that presents stories from the Bible, both having the figures move and a voice telling the story. As I understand it, that was one of the points of stained glass windows, to help those who couldn’t read learn about God. If he doesn’t speak Occitan, how will he get the window to tell the story properly? Whereas if he was attacked, he would much prefer to go invisible, start casting The Call to Slumber and mostly let the companions and grogs handle it.
Finally, I think it is a mistake to think that simpler character creation leads to more popular games. I love Feng Shui and like Unknown Armies. Are they more popular systems than Ars Magica? It doesn’t seem so. This discussion board is way more active than those, but that may just be because as those games are simpler, they have less rules discussion. However, when I look at sites like Pen and Paper Games and look for what games are looking for people, I see a lot more Ars Magica games than Feng Shui or Unknown Armies or Over The Edge. Not that I see a lot of Ars Magica games, but at least I see a few.
I think this follows from two things. One, I think many people who game enjoy putting effort into the game. They enjoy thinking about their character, considering what he is like, how he could become more powerful and how cool he is. The more complex the rule set, the more they can spend time doing that and the more objective the result seems. For many people, this heightens the enjoyment. Secondly, part of the appeal in table top gaming is social. Having information that those in the group know and talk about and those outside the group are ignorant of is one of the ways social identity is built. This is true for church membership, football fans, people who watch Lost, and so forth. If the activity doesn’t hold enough complexity to distinguish between those who understand and those who don’t, it fails in that respect. Also, if disagreements can be settled by an appeal to an objective standard, (the RAW, the Bible, having the football teams play against each other and see what happens) allows conflict to be handled in a less personal manner. Games which are too simple and leave a lot to the GM’s whim don’t provide this, and will likely be less successful as a result.