Ukraine's economy is on EU and North American life support. It's in no position to exert economic pressure on Russia except by bombing Russian bases in Crimea and Russian ships in the Black Sea that make oil tanker insurers flee. You're conflating military and economic pressure. Ukraine's HIMARS and crowd funded drones can't exert economic pressure.

The ruble rising too much is bad for Russia because the $ from sold hydrocarbons buy fewer rubles to pay salaries, pensions, weapons mfrs, etc. That's why Russia's central bank lowered interest rates. They overshot their objective of saving the ruble from crashing by using capital controls, all but shutting the stock exchange.