Sadly I think there is too much battlefield asymmetry for Ukraine to succeed in a traditional maneuver warfare. There was a brief window a year and a bit ago where a major influx of Western equipment "might" have tipped the balance while Russian forces were still disorganized and not dug in, but that ship has sailed. The only vulnerability is Putin's standing with the general public, particularly in Moscow. The war for all practical purposes does not exist for the average Russian, but that would quickly change if they like most Ukrainians, they are running to the bomb shelters every day. If Ukraine were supplied with a large array of long range precision weapons and told most of the don't fire on Russia restrictions were lifted I think Putin could be driven to the negotiating table pretty quickly due to popular unrest when the war becomes real to the average Russian. However to do that the West would have to call Putin's nuclear bluff, and I just don't see any Western leader willing to do that.
Sadly I think Ukraine has past the point of no return. They don't have the population to defend such a long front line and the massive troop size advantage of the Russians make a game changing break through increasingly less likely even if the Ukrainians were massively rearmed. Putin is right, time is on his side victory is what ever he decides it is. The bigger question is what is his end game ? Will control of existing territory in Ukraine satisfy him or just embolden him in pursuing other territorial conquests like the Baltic nations ?