itch.io

You can keep the rectangle hitbox, but you can make them smaller than the sprite, this way it's less punishing and frustrating to run into them (and if you want to keep the difficulty, you can make the objects by themselves bigger)

Yes ! It can be a good level design training to make levels where you have to explor a bit more to find the gifts, but by doing so you loose the runner aspect of your game, maybe something like Geometry Dash where the objectives are on an alternate route

Good luck continuing on the game design road!