Have already been fighting as an independent force. They have some battle tested veterans. And in addition to beefing up their combat arms side they have improved their logistics and support capabilities as well. But I still don’t think they could hold up long term if Russia was to commit significant men and equipment? But there are wild cards too? What outside support both overt and covert would Ukraine receive? And what if Ukraine also decided to engage the Russians in Russia? Ukraine lost most of it’s navy in Crimea and their Air Force is limited but they have been investing in drone and hoo knows what else?