It felt a little bit odd that the bee goes so slow up and down, but it's pretty fast going left and right. In the end I used the horizontal movement to dodge the attacks, so there is nothing wrong with that. Also one thing that felt out of place is the heart on the left side in the third or fourth level with a spider right below it, that is the hardest one to get in the whole game. It would be very thematic that it was a 'trap heart', but being that the only one that felt impossible to reach and in one level in the middle is what makes it weird.
Beside those two things, it was quite fair and straightforward. Finding the hidden machine parts takes some looking around, but is not difficult, so well done!