The "luxuries" so to speak that I wish I had when I started...none are needed, but enjoyed none the less....
1- A second RODI unit. Was running a 75gpd unit which was fine, but filling a new tank or after using a full bucket of RODI on a project, it took forever to fill. Won another one from BRS and run them both and I can replenish fast now.
2- Fleece roller. Started with socks, quickly learned to hate them. Fleece rollers cut down my work load so I could enjoy the tank more.
3- Dosing pump- I used to add things here and there, could never be consistent so I didn't see the results I wanted. The dosing pump does it all so I only have to shake a bottle once a week and top off a bottle here and there.
4- A UV Light- first set up I had so many issues I converted to Freshwater. Algae, cyano, it was nuts. Was dealing with an algae outbreak on the freshwater and added a drop in UV to my pump chamber in the skimmer and it was gone within half a day. Started a small reef, added it right away and skipped so many issues. Restarted the large tank as a mixed reef, had the UV, skipped all those issues again. $20 drop in saved so much time, money, and aggravation.
In time it may expand, but for now this is it. I don't test my water enough to justify something like a Trident. I don't need automation or anything else like that with controllers. Who knows what will come out in the next 5 or 10 years though that will make me wish I hade one when I started.