Wow. This game's presentation is through the roof. You're doing this yourself???!!!
Fantastic job with that.
The music is good, the pixel art is excellent, and the enemy design is great.
The power up system you have looks simple and intuitive, but varied.
Most of the gameplay looks great; enemy patterns look pretty well-placed.
Why checkpoints? I understand using them for continues, but being sent back every time you die is quite unforgiving.
For me, they're pretty rage-inducing (make it through a hard section, take a hit, and have to do it again. This is especially painful with bosses).
I understand their use in the arcades. Checkpoints required more memorization, which means more quarters fed into the machine, but I don't think they're necessary now.
If you want to keep the checkpoints, it might be a good idea to balance them a little (Possibly with an autobomb that uses all of your bombs, or maybe getting hit would reset your powerup to default if it was powered up, if it wasn't, you would die, etc.). Just a suggestion. I'm sure there are other ways to balance the game.
Overall, the game shown looks great! The game feels.. well, I can't actually play
it, but it looks
like it feels great.
Keep up the good work; I'm looking forward to seeing what you'll do with this.