I really enjoy the steam-punk games like Battle Garegga but space ships get my preference.
19XX is one of my favorite "old-school" shooter. I don't know how you can hate him. Simply splendid.
Otherwise I'm currently into R-Type Final,Dangun Feveron, Guwange, Gradius V, Armed Police Batrider, Dragon Blaze, Prehistoric Isle 2 and Gigawing and here's my opinion:
R-Type Final: My favorite shooter, that means all.
Dangun Feveron: Excellent music but so quick enemy shots! Must be a cyborg to survive beyonf the 2 first levels in 1 continu. I'm loving it though.
Guwange: My favorite of the moment. Great medieval style and pure manic essence. Screen gets 95% covered with shots but they're slow so it's even more fun to see your character escape a thousand shots wave at last. Very excellent.
Gradius V: Fun but too long. I'm only playing it for some days and haven't passed the section 1-4 and I already find too long. Weapon system is not my cup of tee. Cool but just for spare time.
Armed Police Batrider:Fun above all. Great.
Dragon Blaze: Another excellent Psikyo game here. Great ambiance but enemy shots are coming so fast... Anyway, it's very interesting.
Prehistoric Isle 2: Ha ha, this is easily the shittiest game in the list. Awful graphics and kitsch theme simply gun down this game. Horrid.
Gigawing: Another heartbeat here. I love the reflect force shiled. Great music and graphics. I love it.
Oh, and for those you haven't tested Radio Zonde, give it a try, would be interesting.