As an average Joe angel (not blessed with any inherited wealth), I personally think it's fair ask to ask founders to vest a "majority" of their shares. IMHO, if angels take 10% for a company in its infancy and leave founders with 90% vested equity, there is simply too much risk if one of the founders decides to leave! Especially so when the business itself hasn't really been properly built.
As someone who started the first travel site on the web (GetThere) and built it to 600 employees, an IPO and later sale to Sabre, and who debated this with my co-founders and myself, there is a most definitely a happy medium (we started with 18 months of vesting on a 48 month plan).
If founders start 100% vested then the pre-money will simply be a different calculation, and founders will earn additional shares to continue to provide incentive post-funding. Don't delude yourself that somehow your equity will provide sufficient incentive for you to continue to perform. This might be somewhat true in startups with one founder, but it's considerably less true when there are 2 or 3. And it's also protection for you as a founder. Why let one of your co-founders be able to cut out early on and get the same deal you did when you still have to put in the time in order for the opportunity to truly prove its potential. It's important for the founders to continue to vest-- and also, when things take longer than 4 years, as they did for us, more shares are appropriate for founders that remain essential to the business.