Maybe make it modification based to make stock grinding bearable.
Helis should, much like planes these days, already come with some weapons stock. Fe. you get 4 Hellfires stock, researching the modifications would allow you to carry more, much like top tier planes now basically always have a pair of ARH and IR missiles stock, with modifications allowing you to carry more of them.
good idea but for ground too (stuff like the lav-ad etc) for planes is should be based of the things you can’t change like the a-26 and its cannons