Very simple way to figure out the question,
If you went back in time, would your audio purchases differ in any way--with what you know now? For me, they sure would! Not with amps or CD players, those would remain the same for the most part. Speakers is my black hole that drained my wallet, time and caused grief. My issue was ignorance of what I wanted the speaker to do and underestimate my needs that I didn't understand. My first speakers (beyond the boom boxes) were very good but lacked in SPL, deep bass response and style. (I was 21...sue me!) I replaced them with stylish speakers with higher SPL capability and a very stout amp. However, they did not have the bass response I assumed they would have--and they died a horrible death within 18 months. So, I learned the hard way that I needed both larger and more efficient speakers--only blew them up 3 times in a year of ownership. After burning the voice coil on the woofer, replaced the driver and sold the speakers--it forced me to do a terrible thing! I bought a book on audio, speaker design, setup, how drivers are made and all that jazz. After a few books, I then realized I could not get speakers that could provide all my requirements in one pair--and fit where I lived.
So, I bought a small pair of speakers that had great sound quality, no bass response and decent but not very high SPL capability. I then mated them with a subwoofer, did the crawl and EQ to get that system to sound as good as I could (with limited acoustic panels and tricks) To get high SPL for party mode, I purchased a pair of 3-way 15" PA speakers and high passed them at 40Hz to protect the woofers. The PA speakers made great speaker stands for the much smaller sub/sat system and I was content--for the next 10 years. The amps/pre-amps etc. went away once my kids figured out how to turn it on so I put that system away and went with an AVR in 3.1 mode--moving to 5.1 mode years later once they understood it's operation. That AVR was used for 15 years so I got my money out of it! The mega amp I used drove subs until it fried...call that a win.
These days I do the same concept, the HT system in the house with an AVR, very efficient speakers and subs. The crazy train is out in the garage with old school amps, pre-amps, some EQ and large speakers and subs to play around with. Just like in my early 20's, one smaller system to do sound quality and clarity with the garage system to go full rockstar block party mode. I'm wise enough to know to have the party in the garage instead of the house because a spray hose can clean your garage easily.
My greatest regret was to not purchase, read and understand a few audio books I used to define the correct design requirements I needed from the start. If I did that, it would of saved me quite a bit of money, time and aggrivation by getting the proper speakers first. I admit it, I could of skipped purchasing 3 pairs of speakers and spent that money on something completely useless...dating! Since I have an electronics background, I didn't waste money on cables, amps and CD players--I'd still purchase the same ones (maybe a little less on the cassette deck--get off my lawn!) After reading a few audio books, I was smart enough to get an SPL meter, an Autosound 2000 test CD and the art of learning and correcting things really helped with home, PA and car audio games.
The best audio component I ever purchased happened by accident. I had $90 worth of stuff in my Parts Express cart which would of cost $17 in shipping. If I bought 99 bucks worth, free shipping so I looked for a gadget to get me there to save 13 bucks. The Lepai 2020+ with 13.5V 3 amp power supply was on sale for $19--why not? The cost difference was about $6.50 because of the free shipping so off I went. In the past 5 years, I've used it to test speakers (it is stable to 2 ohms) check subwoofer builds for friends in their cars, ran speakers from it off a car battery, used it when I'm filling the air with sawdust and general screwing around. The teenagers would crank that poor thing for so long the chip would mute the output allowing it to cool. About as close to idiot-proof as you can get and it gets the award for most abused audio component I've ever owned.
Biggest regret of a video component was a Laser Disc player--heavy and built like a tank but... I lost the thrill after owning 5 movies. Fun to scare children with, the huge tray and the giant, shiny discs give an appreciation for improvements in technology. This is NOT a record!
If you don't have any regrets after doing something over a long period of time, you are not doing it right At least I did better with audio than with cars and women--we don't need to talk about that.