well ... the tooltips aren't exactly refeclting how the faction are in game and I made a post about it.
Vanguard have strong ships, use mostly guns/missiles and in lesser extent beam weapons
Deprived have the ability to regen life/armor out of battles but do so by cannibalizing their max armor, so the more they regen the less armor they have in the end. they are pretty harmonized with what weapon their ship can use.
Eclipse, have stronger shield/shield regen than most others, tend to favor beam weapon. but unlike stated on their description they don't have any penalty to how much gun they can bring on a ship compared to other faction.
a tip to make easy money, play with a friend in coop hard, both of you, use Eclipse and as much possible ultra range laser, use some small ship to scout, and let your fleet rape any enemy ship coming in range.
Use that money to open 4k packs rinse and repeat to unlock most techs.
Best ship(in my opinion and after extensive test over past alpha) would be a Timur with a full set of long range heat laser + fleet jump. once you have 3-4 on the map you melt all the waves, if both you and your friend have them you can just afk until wave 10 ... lol.
you can add to that some cheaper vessels with also 15-18k range laser and it would do the trick.
if you have load of cash, in discovery you can find black markets, easy way to get some missing techs blueprint is if you go with a friend you also can sell to black-market all the blueprints you already own and your friend can buy them off the market, same the other way round if your friend has tech you don't.
Cheers, otherwise just build and try things, they add/balance many mods between alpha. I saw at least 4-5 new ones this alpha only.