Why do you get softlocked if you die to the amazon boss
Why do you have to go to one stage to get warped to one of the other stages so that you can go through the mirror that was previously just a one-way teleport destination
Why is the last stage just one of the previous stages again
Why does the last boss fight just involve climbing up a rope with no obstacles
It's ok

There isn't much about this game that stands out but it's pretty fun.
Many of the enemies are extremely derivative of those in other games. I'm pretty sure the bats are ripped straight from Castlevania and one of the other enemies is traced from the player sprite in Contra.
There's a shump-esque satisfaction to exploding dudes and the upgrade system, especially after suffering through Power Blazer.
None of the stages or bosses are particularly challenging (except for the second for some reason?) or memorable since they don't really follow a specific theme (ex. in Power Blazer, one of the stages has some kind of bio/organic thing going on with plant enemies and boogers that fall from the ceiling and a boss that's a giant beehive. In Power Blade, however, this tileset is not utilized as much for that boss's stage and IIRC also appears in an optional area in one of the other stages?).
There's an "expert" mode but it doesn't change anything besides adding Castlevania-style knockback (but only on certain hits?) and making the time limit much stricter, which does make for some close calls but usually doesn't pose much of a threat.
Music is pretty good I guess.
I suppose it's nice to play a NES side-scroller that doesn't put up much of a fight once in a while.

This game is not very good!
Way too tight jumps for your guy's tiny little jump. There's a part with falling spike traps that requires pixel-perfect precision.
There are power-downs!
The last boss has like 10x more health than it should. Genuinely the worst damage sponge I've seen in any game ever. That alone brought this game down by one star.
Just play Power Blade.