While your ideas would make the game "better" for the user, they would make the game much more difficult to maintain and grow for the developer. Game development costs money - plain and simple. Game development for WoW costs a LOT of money. Think about all the new content that comes at no extra charge every time we get a content patch. Ulduar wasn't free. Your monthly subscription fees pay for things like developers salaries, server maintenance, hardware upgrades & repairs, and even things like custodial services & utilities for the Blizzard facilities. That's right - cut out the monthly subscription for WoW and a janitor could lose his job. And for what? So that people like me & you can have an extra 15 bucks a month to blow on lunch at Chipotle instead of leftovers, or another Barbie/GI-Joe for our kids? No thank you.
WoW has charged $15/month to play for over four years now, and they because the most successful MMO ever doing that. They've brought players top-quality product from day 1. I, for one, will gladly fork over my half-hour's wage for yet another month of doing something I really like with people I really like in a medium that I really like.
Now, that being said, your point about Classic servers has a lot of merit. That discussion always has. Many people who want classic servers have even said they'd pay a small premium to do so. I would agree that it would be a totally feasible thing for Blizzard to undertake, and even then I don't think it would really be that much of an undertaking. Unfortunately the only things you can do are those that have already been done - i.e. forum posts, blogs, GM tickets, etc. Maybe someday they'll come 'round, eh?