Ukraine is actually perfect...
Putin bit off more than he could chew... His army could be decimated here while West would be just recycling old weapons..
My suggestion would be to have a Mercenary Air force put together and paid for by Ukraine(Donations from US & EU)..
The idea of leasing an air force to Ukraine could solve several current challenges on the issue of military support. And some discussions have reportedly already taken place.
www.kyivpost.com
Then give Ukraine the Artillery they need... If they need help we gather up up a Mercenary Army training units...
So how do we get those units fast...
Ukraine (with the help of US and EU) come together what they need. Equipment, a list of various people and the skills they need...
The military then find within there armies the men who have the skill they need. They approach them and ask them would they like to volunteer for a mercenary army and they get extra pay and the experience would be good for there career. The would be given a sabbatical from there home country army and they join the Ukraine Mercenary Legion.
Only one major caveat, these guys are going to be paid multiple amounts of the Ukrainian Army so use them in specialist roles like Trainer, Warthog Flight Mechanic, Warthog Pilot... Basically stuff a Ukrainian will say, we have no one to do that and we are grateful they are here.
Do that, Putin can't object to mercenaries (he is using them himself), this is not other countries fighting... But now US can put any weapon on the field and have trained people in place within a week... Need Warthogs, have them in a week and withdraw them in the same time...