while the recipes in the "higher-end" type of books make things interesting, that type of cooking isn't necessary for a balanced diet. i can't say that what i did in college ensured i got enough of every nutrient, but i got the food groups:

a salad as a meal - whatever lettuce, dressing, other veggies happen to be cheap. i think it's a good idea to 'invest' in getting some variety of stuff for it, because it'll keep the salad interesting and unlike the gross restaurant-style iceberg-carrots-cabbage stuff. Even a more expensive type of ingredient like avocado can be spread out over ~ 4 salads. I think raw veggies are better for both budget and dieting because cooked vegetable loss volume, so you'll have to eat more (-> spend more) to feel full.

for fruit, bananas are generally inexpensive and roughly the same price/quality all year, instead of keeping track what's in season and on sale. Cheaper seasonal stuff like apples, pears, and oranges are good too.

for a heavier meal, i have to say... beans and rice. as far as balance goes, legume + grain + possibly more vegetables if you can do it. If you have a kitchen, cooking beans from scratch is cheaper than canned and not very labor intensive (as long as the pot doesn't boil over, you don't really have to do much), and you can freeze extra for later. A pound of beans makes about 3-4 cans worth, and doing it from scratch means you can keep it low salt or season to taste. An added vegetable can be whatever happens to be on sale, or frozen mixed vegetables (not the tastiest, but it works, and is often sold in 2- or 3-lb packages). If there are "ethnic" markets near where you live, they might be worth checking out because they can have pretty cheap vegetables, including "fancier" ones called for in cookbooks. e.g. Asian markets near me sell shiitake mushrooms for $3/lb (around the same if not better than white mushrooms), whereas health food stores sell them for 8-12$/lb.

If you live near one and know someone with a membership, Costco has apparently vegan whole grain bread that comes in two packs, and is pretty reasonable in price. If you have one, you can keep it in a freezer so that it won't spoil and you can just toast a couple slices at a time.

To keep things interesting, condiments and spices. They're a bit of an investment at first, but usually go far and not too calorically significant. Some brands of spices/herbs are waay cheaper than others, too. The little jars in the aisle at the grocery store (McCormick, etc) are more expensive, larger containers (like Delish) or bags at the end of the aisle are usually cheaper.

As far as specific recipes, a lot of the highly-rated vegan cookbooks aren't about minimalism but more about showing how varied/nice/interesting vegan cooking is. A book specific to your needs like Jesse mentioned or vegweb recipes will probably be closer to what you're looking for. though fake meat/dairy stuff is fun, it isn't necessary for a good diet, is generally more expensive than eating more whole foods, and in some cases is just extra calories that don't need to be there. However, getting something like that once in a while can be a nice treat and can be spread out (tofutti cream cheese lasts forever).