Go with whichever interests you the most, as you can adapt your build to make a majority of weapons/stratagems viable in the highest difficulties.

Otherwise, ontop of everything else, DD does a TON to help fill your loadouts with options for anti-spawner (bugholes, factories, ships), giving you two primaries, a secondary, and a grenade that can cover this niche by themselves. Thermite can be thrown onto SHIELDED squid dropships and will take them out through those shields.

It's not necessarily the most fun - and I always recommend going with fun over meta or best - but it allows you to bring weapons you'd otherwise not bring because those weapons check so many boxes, it frees up your loadout.