Psyvariar's colision detection was excellent, the hitbox of the craft was ridiculously small (for Revision, at least) and you could do suicidal maneveurs in the middle of a sea of bullets. THAT was the point of it all. I haven't played Psyvariar 2, but the focus of Psyvariar was buzzing, buzzing, and buzzing. More than killing enemies. The more you buzz the more points you get, and you're able to access zones you were not allowed when you achieve high scores. So the point is buzzing and not dying. For that you have to combine slow and normal modes (when slowing down you can control your ship much better and you're buzzing twice as when normal). You shouldn't kill enemies until they've fired some shots if possible. Memorization helps, and reflexes are vital. You'll notice that when levelling up your ship becomes undestructible, which you can use to actually sink your ship into those crazy bullet patterns and level up again (in a matter of a second) and maybe again and again. Chaining level-ups is the only way to beat some bosses without getting killed, unless you use some of your bombs in a very smart way.
All of the above applies to the Revision of the original, which is pure fun. As I said I have not played the sequel (yet), this advice may help or not. Anyway, Psyvariar is an incredible shooter and deserves all of your (our) love.