I've booted this one up a number of times in the past, but I don't think I ever quite finished it. Unfortunately, the time that's required to beat the game reveals the subtle input issues that hold it back from being as slick as it means to be. Ranged and melee attacks (and sometimes even jumps) have a stickiness that belays the player from flowing into a high combo, but the design of flow is clear to see even if it's irksome to achieve. When I played previously, various elements had been erroneously surmised as an endless structure without a boss fight, yet different game modes could easily be validated with some alterations to the score and states of loss.
The game uses the shell of a skating Nerve game to facilitate a unique form of beater that actively ignores typical assumptions for racing-adjacent mechanics; use of the dash is essential for retaining speed by correcting course away from walls or onto midair rails. Stomping on enemies with a simple jump would be an economical addition for further retaining a combo, although such changes may not have been necessary with cleaner inputs.
Jet Set Radio Future's apparent design was that simply skating around was the priority before any other game objective, and this clashes notably in a handful of frustrating level segments with tricky jumps and long setups. Thankfully, like most Nerve games, the requisites of flow are immediate and apparent, meaning the objective is more or less always in front of me by nature of my inertia; by contrast, scanning the level for an enemy to poke with a ranged attack requires a difficult cognitive switch, and the small persistent icon for enemies is a translucent yet vital interface for supporting this objective.