The speed starts off WAY too slow, like unfun levels of slow. You’d want the base experience to be fun and enjoyable within the first few seconds for people to bother staying around, which is likely tanking your average.
Unless I stay and build up my character to a point where the game is fun, there’s no reason for me to keep playing or even return at a later point, since my initial experience was sour.
I would recommend you start off by improving that core experience, make the base movement enjoyable to move around. If the base movement is enjoyable, I’ll stay longer to experience the upgrades.
Just before it starts to get boring, I should unlock a new upgrade, movement ability or skin to keep me playing longer by saying “Well I DID just unlock this, I should at least stay and try it out” and before you know it, I’ve been playing for 3 hours.
That wouldn’t really address the issue, the problem is the starting speed, not really the rate of upgrades.
It felt really sluggish and boring, I didn’t even want to bother trying the levels because there was just no fun in the main part of the game, which is the movement. The movement has to be enjoyable out the gate, you have maybe 15 seconds to capture their attention with the movement or they’ll just leave unsatisfied.
The starting speed should feel at least faster than walking and ideally would have a slight hover to it. If there’s no fun in the movement, why would I bother grinding up the levels? I can join any game for an obby experience and plenty of games will give me a decent hoverboard to ride.
Your experience has to stand out with the movement for anyone to bother returning and even more importantly to bother staying and playing.