Idle temps are perfectly normal for windows 10. There's enough crap that runs in the background, that constant program startups will constantly bounce your temps from idle 32 to small load startup 55. But thats such a small load that the temps drop a second or two later, no worries.
It's the 90 that's the issue. With just 2 fans, airflow isn't optimized and that tiny CoolerMaster isn't much more than a 'stock cooler' would be. Ok for websurfing or other light cpu usage, but under duress, plain sucks.
Airflow needs to be better, adding fans is good idea. If going with an aircooler. Aio has included fans, so the budget becomes more equitable. Honestly, I'd slap in a fractal design Celsius S36, 360mm radiator, for a cleaner look with full front matching fans, move the current intake to exhaust and never worry about temps again.