There's obvious pressure on Russia in Luhansk, Donetsk and Kherson.
As Russian power erodes there, they will be forced either back across the border into Russia, or back into Crimea. To me, it looks like Crimea will be their last redoubt in Ukraine. And the narrow neck of the peninsula will be heavily defended. So that last part of the liberation of Ukraine will be far the hardest.
On the other hand, HIMARS.