With only hints of need from you its pretty hard to make good suggestions. Tactical seems to be your main interest though.
Sounds like you have your heart set on an AR, so that should be a no brainer for you. I'd rather have the Garand myself - I have no use for tactical.
No rimfire handguns is a big hole in a personal arsenal IMO. A cheap way to spend a day shooting and honing skills. Wish I'd never sold my Colt Ace, but a 1911 with a rimfire conversion kit would be a pretty versatile handgun. One well worth a looksee is the KelTec PMR-30. Tactical, hunting and target shooting all rolled into one handgun with a 30 round magazine.
Shotguns is another big hole. Which one depends on what for though. I always favored the SXS's and O/U's myself, although I've had auto's, bolts, pumps and single shot's. But then I only used them for hunting and shooting trap and skeet.
Also missing is any lever guns. Growing up on a ranch with Winchester's means my early 40's 94 I've had around 56 years will always be the top dog, but there are a lot of good ones out there from several makers, and chambered for quite a few cartridges from rimfire to cannon.
My thing since the mid 60's was specialty single-shot handguns, and many will stay with or surpass rifles to very long ranges. There are models made that can cover well over 300 cartridges from mouse to mastodon between them with only a quick barrel change. Very versatile from plinking to target to hunting to sniping.
Have fun shopping all possibilities first before you decide and you will have made the right choices for you. I did similar in 2004/05, except I didn't have a budget. Was like a kid in a penny candy store, had a great time and spent 10's of thousands on new guns, scopes, reloading dies/supplies, etc for them (so many I still have some NIB I never got around to, and others were resold still NIB that I knew I never would get around to).