Different Tier ship upgrades?

When adding technology to a ship, can you have like number max S-tier upgrades, aswell as the max number of A-tier upgrades at the same time? is this how you get god level ships or should i just fill up my slots with S class stuff without overloading it.

just seems odd to be able to have 60~ slots for the tech but not be able to fill them all unless you can add different tiers