I don’t see why it wouldn’t be acceptable to pray to Hashem for a husband with healthy eating habits who is not overly dependent on his wife to eat healthy.
The fact is, a certain number of men 1) have no clue about cooking, and/or 2) are extremely picky and only like a few foods, like ones associated with men like meat and potatoes. However, nowadays there are many men who like to cook, including vegetables, and who eat all kinds of vegetables all the time. In fact, there are even frum vegetarians (or near-vegetarians.)
You can try to find a husband who loves veggies and knows how to cook, and I’m sure there are many such men out there. But even if you don’t, as you mention, perhaps that is something you will contribute to the relationship — healthy food and other habits.
Unfortunately, many men today eat a standard American diet and have little exercise, resulting in shortened lives through cancer, heart disease, obesity and diabetes (and, I would, add, a less sharp mind and earlier mental decline, damaging one’s ability to engage in Torah study and prayer to the best of one’s ability). It is alarming how many men have large pot bellies by the time they’re in the 30s or 40s. But many men are more health oriented and realize they need to exercise and eat differently.
In Judaism we are commanded to take care of ourselves very much (“meod meod”), so it certainly makes sense to eat a lot of vegetables and exercise, as previous generations always did before the last century or so. May Hashem find you a match that is compatible with you in every way and who lives a long healthy life with complete shalom bayis!