I do a lot of different versions of this kind of thing when it's just me at home and I want something quick. I basically dump the hot rice onto whatever I am mixing it with and let the rice warm the other ingredients a bit.
Good things to add to hot buttery rice:
Cooked chicken
Ham
Tuna
Tinned sardines in tomato sauce
Anchovies
Feta
Chopped hardboiled eggs
Any roast meat leftovers
Spring onions
Sliced babycorn
Frozen peas/sweetcorn
Tinned sweetcorn
Red/green peppers
Grated courgette
Chopped tomatoes
Chickpeas or other beans
Also, lemon juice, soy, chopped fresh herbs, a bit of squished ginger and/or garlic, lime juice, houmous, sesame oil, mayo, sesame sauce, tahini, curry powder, cumin, chilli (fresh or dried). Not all at once.