There are a few pieces of reloading gear I wouldn't want to go without:
- Motorized case prep center. I have the Frankford Arsenal, it's great, some people go big and get the Giraud.
- Spray case lube. I use Hornady One-Shot, none of that "lubing single cases by hand" garbage.
- Micrometer seating die. I like Forster, but there are other great options out there.
- Redding Competition Shellholders. Lots of people back out the FL sizing die to get their desired shoulder bump, but it's been shown to be less repeatable and really finicky, the shellholders are vastly more consistent and are much easier to use.
- Automated powder dispenser (hopefully you already have one). Tons of time saved.
Annealer can come later if you decide you really wanna do this thing, you'll get a decent amount of firings out of any quality brass without annealing esp if you aren't hot-rodding your loads. I have a chrono but it isn't necessary if you can validate dope at your expected range; back-calculating MV is simple with just about any ballistic solver. You also need a 6.5mm bullet comparator to determine seating depth, Hornady's works fine for me. It might not be 100% accurate, but I believe it's 100% repeatable and that's all you really need; that's why they call it a "comparator."
Lastly, it's crucial to determine your goal in advance. If you say you want the "smallest groups possible," you'll never be finished with load development, since you'll always be asking yourself if you pulled that shot or if the load is bad. You need to set an accuracy goal at a certain distance, and keep it reasonable. I'm guessing you're not an F-class shooter, so 3-600 yards is a solid distance to target group size. 600 will do a good job showing MV spread, but it'll also add a fair amount of wind into the equation which can make it hard to tell how good the groups are from the load alone. 100 yards is fine if that's all you've got, but be aware that if your MV spread is sizeable, you probably won't be able to tell on paper at 100.
