That will be a very capable build. If you really want modular, you can also grab the OCZ ModXStream off of Newegg for $35 after rebate with code EMCKCJE26 right now. I have been using one for a year now and recommend it when it is at this price point. It is quiet. 500W for the PSU is of course total overkill for a system like this unless you plan to add a discrete GPU down the road.
EDIT: You could also use a PicoPSU. That would free up tons of room inside the case and take away any heat from the PSU.
