It's fun to think about all these cool combinations of powers, but will we actually be able to take advantage of them? If unlocking powers takes too long, it could be the case that we won't be able to put together creative combinations until the last few missions, and even then many of the combos will remain off limits to us.
Will the first few missions feel less interesting (and less replayable) due to us always having fewer powers available, resulting in fewer options in how we tackle objectives?