There's something about Syrsky that feels somehow more 'modern'. I'm not concerned (not that I've any right to be and my opinion of ZSU staffing is worth less than zero).
But of the two, I suspect in my bones that Syrsky could pull off transforming the front line from how the Russians want to fight into how the Ukrainians can and should fight. That is, I suspect that he will shift the tactical structure on the Ukrainian side from orienting on Lines (trenches, cities etc) to dominating spaces/volumes, avoiding static fixed points for RUS artillery to pound.
Currently, while RUS has the initiative I think its because the ZSU is fighting in the way that Russia needs it to in order for Russia to be able to get the initiative. The ZSU's current configuration values the same things as the Russians - lines on maps, place names, etc. Geography and overlayed political mapping, islands of resistance joined into a web of linear static priorities.
If the ZSU begins to fight in a different ways, like say around Kiev, valuing different things from the RUS and willing to trade what it values less for what it now values more, then they could achieve operational balance before unbalancing the Ivan.
Part of this idea is that the ZSU could deepen the front line zone, ignoring trenches, never staying put and constantly moving within a much broader battlespace. Flowing instead of standing. Utilizing C4ISR to constantly outflank and corroding the 1,2,3 echelons of Russian front lines all at once. IE simultaneously conduct attack-defence in the same zone, at the same time, where attack is defence and defence is attack, in contrast to the simplistic Russian approach focused on progressive subjugation of a series of points and lines.
Mobility would not be forced into or on the Russians but provided to the Ukrainians within their own "side" of the battle space. Blur the operational contact area between the forces and rapidly corrode tactically.
Zaluzhny can see the value of drones and their danger, within his existing viewpoint of military force. Sysrky, I hope, can see a new paradigm - or at least the need and path to one. I think he will initially focus very heavily on the training funnel, shifting to a smarter, more responsive and intuitive process. This will cost him time and space but provide him with better forces in the medium/long term, forces that can handle and expand a new tactical and operational mindset.