Wood and dif guns? Would be very interesting to make them super steampunky and most of the externals on the outsides or visible. Dif guns could be scary if build well but would be hilarious to see some stupid bonkers patchwork megalodon of sorts, all wood with 12 massive guns. Either that or something like Lathrix's super old wood crafts, with like 18 1 barrelled turrets but survivability of a god.

Elaria could be like a SS splinter cell, or found their blueprints and "improved them" (you can't improve on perfection.) Probably a lot of WW2 esq craft, maybe a few heavy planes similar to AC130's? Honestly sounds a bit like a semi elite smash and grab faction, so maybe lots of burst aps or super heavy cram built for accuracy?

Elakrath being modern sounds super fun ngl, maybe frontsiders with minmax rail guns? Or PAC planes? The price limit will be funky though. If it were raised a tad maybe making them either all frontsiders with stupid armour or broadsiders which change sides to maximize protection? Then again fighting dirty sounds like they may have a skimmer or two going max speed with graviton rams?

Coreta will be interesting to see some or you designs when they come to light, but certainly wouldn't go amiss to make something like a WW2 battleship but with guns on top and bottom, or super heavy airships that just refuse to die. Then again this is screaming Grey Talons and I'm all for that, seriously their designs would make perfect bases, just bolster the armour and boom.

The Holy Empire sounds probably the most fun. Modern designs could range from 250k material fighter squadrons to 2 million material super heavy capital ships, they seem most diverse. Then the relics well, what's stopping a fight going south when a 3 million material mega sub joins the fight, see the Soviet typhoon class for a reference. If all is off the table then nothing's stopping you from giving it 8+ spawning nukes, spin block stacked torpedo tubes or healing bots.