Well I'm currently on my third attempt and it's finally going my way, I'm trying to build my fleet around a large core of destroyers and frigates before expanding into cruisers, usually with a draco and flamen wing for harassment and killing the really annoying glass cannon frigates.
Though I typically have issues with biting off more than I can chew in the mid-game and not making it to capitals, but I'll see how this goes.
edit: unsurprisingly back-to-back fleet battles with numerically superior opponents has once again been my undoing, but I had a pretty good fleet going so some thoughts.
Decurion: Expensive way to lose a bunch of crew and two medium weapons. It can get into battle very quickly and has some respectable firepower to leverage, but no ability to sustain that firepower and nothing else will keep pace with its attack, so any given Decurion will overextend, overload and die, even with a long range standoff build, in 1 out of every 2 fleet battles.
Wolf (I): A slightly better Decurion. The Wolf everyone knows and loves now with inconsequential changes to its armor and speed, as well as a medium hybrid slot instead of a medium energy! Unfortunately the Wolf (I) is a pretty straightforward downgrade from the regular Wolf since 50 armor won't make any appreciable difference nor will 10u off the top speed, but the hit to flux stats, and the fact that very few if any ballistic weapons can be said to be any good at all by themselves means this Wolf is even more prone to overloading at inopportune times than the already high-flux base model.
Invictus: Surprisingly decent, an Invictus can traverse the battlefield at a good pace for an Imperium ship, though it remains inadequate for pursuit, the lack of medium slots and only one potential missile slot however mean that the Invictus is stuck only being truly competent at ranges it will be hard pressed to close to, and once it gets there the generous arsenal of weapons it carries will see to it that it overloads within 2-3 seconds even with good flux perks, and then it will find itself thoroughly unable to disengage or quickly vent the flux, and will just die like a Decurion. However I was able to mitigate some of this by making my pair fly together and screen for the cruisers, where they ran into the fact that they have no means to FORCE a favorable engagement, with middling speed and an autoloader for a ship system anything that simply doesn't want to overload under the withering DPS can easily just disengage and the Invictus will be more or less unable to give chase.
Praetorian: The backbone of any Imperium fleet good or bad, it has actual PD, is reasonably priced, reasonably agile, well armed, and not a pushover like some light destroyers, if it were a little bit faster this would be a recurring staple in all my fleets.
Princeps: A Praetorian that trades away all durability for better PD and a flight deck, won't ever make any meaningful contribution to a battle but that's not what you want from it anyways.
Legionary: All aboard the XL Decurion! I kinda like the Legionary, it's far meatier than any destroyer has any right to be, but it has the same issue as the Decurion where it rushes in and gets itself killed all the time, but this manifests differently in the form of a turbo boost that can't be canceled and disables the shields, allowing whatever the Legionary is trying to close with to momentarily stop kiting and simply *** slap the Legionary out of existence. If I could turn off the turbo drive wholesale I would love it to bits, but as is I wouldn't consider one once capitals are involved.
Interrex: The Praetorian's eccentric cousin. Literally just a Praetorian for energy weapons and missiles, fitting the Interrex is kinda awkward because it shares the Praetorian's ballistic oriented hardpoint layout, but with energy weapons. It is basically the fastest II destroyer you'll find, but still too slow and unwieldy for a proper short range build, all the same 4 missiles mean it fills a good niche for providing burst damage.
Falcon (I): I was a bit skeptical of removing the medium energy slots for twice as many small hybrid slots, until I ran it with 4 lux repeaters and a pair of telums. This ship definitely gets my seal of approval, but only because of weapons like the lux and railgun that can really wring some power out of those small slots.
Eagle (I): It's an eagle with a fixed spinal weapon, the weapon is pretty good though, no complaints really.
Flamen: Pretty okay for an interceptor, they do just about everything I'd expect an interceptor to but the lower rate of fire means they do more damage per shot, which I can get behind even if there are far better options.
Draconarius: This...this....THING. I wanted so badly to like these, the pulsar cannons they carry can be so mean to frigates and sometimes even destroyers, but they are basically incapable of killing anything smaller than a Cerberus. I once caught my Draconarius wing engaging a fleeing bomber wing, the Draconarius' almost lost because between the already bad aim of fighters using spinal weapons, and the momentum based physics of the pulsar cannon, maybe only 1/20 shots hit, and the Draconarius just kept taking hits on its unshielded chin the entire time. It's good super early but any other time it's an active detriment to have around because of what it costs you in pilots and flight deck space.
Vicarius: The jack of all trades. The bomber was another unit I really wanted to like, but it was always more interested in using the particle repeater than bombs, and then presenting its broadside to the enemy as it puttered past, another disappointment. The assault was a gift from the GODS, this thing could actually chew through frigates with only minimal support, I didn't even care how slow it was, the payoff when it got into position was too sweet. The support scaled a bit better, being able to effectively punish shielded enemies rather than unshielded ones, I wanted to pair the two wings with each other but never got the chance.
Scutum: A cool idea and neat bulwark, but like the Centurion I just can't find any compelling reason to use it, it's too slow to work alongside other fighters, doesn't have enough firepower to be a good escort, and is too small and fragile to depend on as a PD screen for larger ships.
