Love the art. Gameplay is fun but it feels a little directionless. I understand you are skirting the line between parkour & shooter but it still feels rough. the red graffiti in particular feels completely useless outside of combat-based challenges. the pink graffiti is unwieldy. green is fun but only in a couple specific contexts.
Your difficulty curve starts way too high and you introduce too much at once. you could literally get away with having your entire first area (which you should engineer from scratch and place before the rooftop area) could have just plain combat or just plain parkour with only 2 or 3 of the graffiti accessible
You might not like to hear this but I think you should do away with the “”“open world, hunt for side quests””” philosophy and move towards menu-based challenge selection with a separate free roam mode. At the very least you need to do more streamlining of the process of repeating the same challenge. for example the grabbing tags challenge kicks you out to free roam mode when you fail. you could instead pause gameplay and prompt the player “try again y/n.
Some of your challenges have multiple trophies where platinum gives 3 records and some just have one all-or-nothing challenge with no better versions. I think it’s pretty easy to step your game up here to give people more. when people set personal records for challenges they want to share them too. you should record user’s best scores and make them easy to tab through and screenshot
nitpicks:
jumping feels great but walking feels really strange. a tad slippery to get up to full speed (fine just not to my taste) but you stop instantly. you should try and bring your acceleration and deceleration math to be more similar.
I immediately noticed the lack of +speed on shift (common for fps games with extreme movement speed to have shift-to-stop-sprinting) though I would only worry about that if you have precise platforming
Add bunnyhopping but never expect the player to use it
some of your symbol usage is just too hard to follow. the X means exit challenge when you are in a challenge, but quit to main menu when you are in hub mode