The Tasty Treasures all contain soy flour and corn-starch, which means they are likely high in carbs. The ingredients you want to avoid in cat foods for diabetics are wheat, corn, soy, and rice.
I currently feed Bandit about 2/3rds Merricks--Cowboy Cookout, Grammy's Pot Pie, and Surf and Turf (for the high protein, low fat, low phosphorus content) and about 1/3 Fancy Feast Classics (for variety). Lately I've been substituting the Sheba premium pate foods for the fancy feast sometimes (NOT the Sheba premium cuts which are higher in carbs and have similar looking cans).
With the premium foods, I've tried Wellness, EVO, Blue Buffalo and NV instinct all at different points, and the Merricks was definitely the winner for us. The higher fat in the other premium brands caused some upset in Bandit's GI tract, but most cats handle the fat fine. Bandit has a history of obesity and triaditis so his needs are a little different when it comes to lower fat. I would get a few cans of each and see what your cat likes, and how he handles them.