Has he tried proper carbonara, that is egg, cheese and bacon/pancetta, no cream?
As he likes bolognese, how about other proper ragu type recipes, but with lamb, or venison etc?
Roasted veggies - aubergine, courgette and peppers, roasted so they’re wonderfully soft and flavours intensified just stirred through pasta and lots of grated cheese on top. Maybe as a bake, seeing as he likes lasagne?
Come to think of it, any pasta bake? I like broccoli, red pepper & cheese. Breadcrumbs or polenta on top for extra crunch texture.
Blue cheese - sometimes I’ll literally just grate/crumble blue cheese onto hot pasta and it melts enough to be it’s own sauce. Couple of olives & sundried tomatoes mixed in too mmm!
Just garlic, lemon juice and olive oil can be nice too if you have really good pasta. I like this with peas and bacon bits too.
I like a lot of recipes with smoked salmon, prawns or tuna too but if you don’t like seafood that wouldn’t work for you!
Different homemade pesto recipes - I like an aubergine and rocket one.