i have never been to table 52, so i cannot attest to that one.
cafe des architect has great food, romantic ambiance, and it feels more like a "fine dining" restaurant. carnivale, on the other hand, is more casual, more lively, and the decor more imaginative. the food and drinks in carnivale are also more unique.
to conclude, go to cafe des architect for a more classy and fine-dining french/american fair in a quiet and contemporary chic surrounding . go to carnivale if you want to try something new and have some wow factors in an energetic and colorful setting.
personally, i prefer the carnivale experience.
All three are restaurants I like.
Totally different food and atmospheres though
Cafe - french brasserie idea in a phenomenal space and terrific baked goods (breads and sweets)
Carnivale - latin fusion cuisine in a raucous get up and dance around the restaurant feel
52 - comfort new american in a more laid-back space