Dilution is a serious matter that should be voted on separately of delegate approval process.
Delegate selection is equally serious.
Here we agree!
What about the separation?
Assume things are separated:
1) Users now vote on budgets separately from delegates.
2) Users now have to consider every individual on the budgets.
3) Proposing items to be included in the budget becomes becomes a challenge.
4) Delegates will end up trading budget items (I'll approve your spending if you approve mine)
5) Users will be left to vote for the same or similar sets of budgets because they were all filtered by the same/similar sets of delegates.
6) Users now have to review every item on the budget (which could be in excess of 101 delegates).
7) Changes to the budget are very slow because it requires share holder approval again.
At the end of the day you add bureaucracy to the DAC. If a delegate cannot be trusted to honor a his campaign budget then he should not be a delegate. If he can be trusted to honor his budget then there is no need for the bureaucracy. If you can have 101 individual budgets each 1% the size of the "master budget" you have far more flexibility.
If and when a consensus model allows delegates to be removed from block production, then that is just one less job they would have to do and the network can continue to function.
I think the goal is to give each delegate control of a percentage of the budget proportional to how much the community trusts them. Asking for direct democracy on proposed budgets is intractable.