I've been in the reloading hobby since IIRC the early-mid 1970's, and have yet to load even one box that I did not label with the following info. And I've not used any press other than "Lee" models since I started.
Labels included: Date of loading, caliber, powder, charge weight, bullet weight, bullet brand, primer brand, COL. There are many pre-printed labels available for purchase, but I made mine up not long after I started re-loading and just printed them off as needed.
The only exception to this is the loads for my silhouette competitions back in the late 70's through the late 80's. All practice loads were labeled, and comp loads done on Saturday night for Sunday comps were listed in my log book, but not shown on any boxes used for the day's comps.
One thing I noticed you didn't mention in your list of things to gather was a case trimmer of some sort. Consistent case length is important to ensure consistent ammo. And let me congratulate you on using good sense in your selection of equipment. "Lee" stuff is as good as it gets, more often not as sophisticated/complicated, and far less expensive than some others. This is not to say any other brands are not good, or as good, but I'll guarantee they're more expensive.
The "Pro 4000" is a great progressive press ...... you won't regret it. In fact it may be way more press than you really need for the amount you'll be loading.
With all due respect, consider that if only loading one caliber and no competition is involved, you may not really need a 'progressive' press. You might want to take a look at the turret press ...... not a true progressive, but is capable of loading some impressive numbers in a short time with the right accessories.
I've recently built myself a roller cart mounted loading station using a simple little single stage "Lee" 'O' frame press and can easily load a couple hundred rounds in a couple hours after dinner. However, just last night I loaded 100 rounds of 9mm and right now I'm down to my last box of small pistol primers. When this 100 are used, I'm out of business until primers are again available. Good luck, good loading !!!