Partial wet diet better than all dry diet for overweight cat?

I have two cats. One is at a healthy weight while the other is quite overweight and has easily gained weight since she was young. She has never been free fed and the amount of food she eats is regulated at meal times to a scant 1/4 cup dry food twice per day. She is a domestic cat, about 11 lbs. 

I would love to feed my cats the best foods, even make them food myself, but I am on a tight budget. Switching to a cheap all-wet diet for the both of them, at 50¢ USD per can would more than triple what I'm paying now for cat food. For me, that's just not sustainable at this time.

I would like to be able to change the diet of my overweight cat, but the healthier one won't eat out of his own dish if he knows she's getting something different. Especially because he's much more fond of wet food versus dry than her. (I've tried this many times, in many ways.) 

My question this: Would a diet of 1/2 wet and 1/2 dry be better than a more strictly regulated dry diet? If I get cheap wet cat food, is the extra cost worth my trouble?

Welcome to The Cat Site.

One half cup of dry food may too much for your cat; like people, metabolisms vary widely among cats.

Wet food is usually more filling, less calories, than dry food.

A diet of 1/2 wet and 1/2 dry [i.e., 1/8 cup of dry food] is better; the more wet food the better.

PetSmart's house brand (Authority) is a pretty good food, as is Fancy Feast classic.  The extra cost of food may save you more in vet bills, down the road.

Friskies pate isn't too bad either (and I assume that's what you had in mind because you said 50 cents a can), but try to avoid the fish flavors.

And, yes, 50/50 canned/dry will help her lose weight more than just dry. Canned food has fewer carbs than dry food does, and the water in it makes it more filling.