Well, I agree with your point about flexibility, but I wouldn't say that flexibility is purpose-building
(but that's just me teasing you !)
Still, I'm really not feeling upgrades being so important in defining the role of a ship (give an edge, sure, but defining, not really), so I tend to fly very very light. (No more than 3 upgrades + titles on large ships, 1 + titles on small ships)
Out of curiosity, what's the loadout of your MC30 ?