Outside the shack: got my antenna up HIGH. 65ft, give or take, according to my plastic protractor theodolite
Obviously a shit hot antenna is always going to be #1. Ideally everyone should simply put in a 100ft tower with a SteppIR or some other monster 40M and up Yagi or the like. If everyone did that we'd have nary a discussion about propagation or QRP. But, failing that, you must get your antenna HIGH, consider 50ft an absolute minimum. Buy/build/beg/borrow/steal, but get it up HIGH.
Inside the shack: bought some shit hot speakers. JBL LSR305 self-powered studio monitors. Blew $250 for a pair off of eBay. BEST $250 I've ever spent on amateur radio, I shit you not. If everyone used these speakers and bought any one of the top 20 radios on the Sherwood Engineering rankings we'd have nary a discussion about receiver performance. They work great for music, too
Honorable mention: bought one of the top 20 radios on the
Sherwood Engineering rankings. Any of these top 20 will make any of the lesser radios seem deaf as a post. I had an IC-7000. Couldn't understand why I couldn't hear anything. Bought a Flex-3000. Could not believe the difference, it was that dramatic.
Starting out in HF? Just go buy an IC-7300 [/mic drop] It's in the top 20. After that, when you start to move up in the world, you can choose another from the top 20, but IMHO nobody should start with less than an IC-7300 unless they are absolutely hand to mouth but still desperate to get in the hobby (no disrespect meant to anyone who is struggling for money, life is not easy). Used 7300s are plentiful and south of $1K.