With the right building blocks, you can get away with making the same dish in different variations. In your case, making a version of an open-face sandwich with diverse toppings can be a good low effort option.
STEP 1: Select carb vehicle (sourdough/rye toast, crackers, pita bread, tortilla(s), lavash etc.)
STEP 2: Add spreads (hummus, grainy mustard, mayo, cream cheese, labneh/plain greek yogurt, bbq sauce– whatever floats your boat)
STEP 3: Layer roasted veggies (two options) 👇
Option 1– Buy pre-chopped veggies of your liking (zucchini, peppers and onions are amazing when roasted), toss with some olive oil, season with salt and pepper/other seasonings and roast in your oven for 30-40 mins at 375ºF or until slightly charred and soft.
Option 2– Most asian grocery stores have food bars with cooked veggies. Buy a combo that is loaded with veg and use those vegetables for meal prepping.
STEP 4: Add protein (roast beef, smoked salmon, grilled chicken, spam, canned tuna or whatever other low-effort, pre-cooked protein you prefer)
STEP 5 (optional): Add any extra toppings/garnishes (pickled onions, beets, furikake, sesame seeds, toasted nuts... I'm sure there's more I could list, but my brain is drawing a blank atm)
Enjoy! Hope this gives you some inspo :)