I'm not sure, I think being able to see future upgrades are nice so you have something to work towards, although hiding the Better Passive Spawns until after buying the first passive ball would be perfectly fine.
I do agree the blue ball should have something to make it different than the standard yellow. If you're up for suggestions then an interesting idea I had would be to turn the pegs that the blue balls hit into blue pegs for a short time (that can be upgraded) and when other balls collide with the blue pegs it can award some cash (which can also be upgraded) not sure how practical that would be but it seemed like an alright idea
edit: I completely forgot the gold pegs existed when I suggested that LOL I guess it could still be possible but I feel silly now