If you don’t already have an AR, get an AR.
A .223 is a good choice to step up. If you can swing the extra $$$, do the AR rather than the bolt gun.
I did the garand thing, but I was a younger man, and the civilian AR was not yet available. As soon as a HBAR AR15 became available, I sold the garand, bought a colt HBAR A2, and never looked back and never had any regrets about it. A Garand is still fun, but I would not recommend it as a first center fire rifle in collection.
With a flat top AR you can do iron sights, scope, or combat optics. Buy the AR, and work with iron sights you'll surprise yourself what you can do. You can save $$ to upgrade to scope later.
If you are interested in punching groups on paper at 200 yards or less , 3 - 9 power anything will do. The Nikon buck master has good clarity. More magnification will get you smaller paper groups. 4 - 12 X will shrink goups a little more. For range queens, I put cheap Tasco variable up to 24X or 36X, and run them at 20X for load development
If you want to do a bolt action, Savage with accutrigge is a good choice.
But also consider a Remington 700. In the last 18 months (so recent data points) between my brother and I we have five Remington 700's that are shooting sub MOA, after some easy modifications. Buy the one with cheap plastic stock. Toss stock and put it on Boyds laminate ($120 to $130 delivered) and add a Timney trigger. ($120)
My heavy barrel .308 is shooting 1/2 MOA in a pillared not bedded laminate stock. It has a Vortex on it. I bought this rifle to build a 6.5 creedmore on, but the .308 shot so will it has stayed as my 1000 yd rifle.
My light barrel 308 is shooting about 1 MOA with Laminate stock, and the tuned factory trigger.
My brother did a Remington light barrel .223, put in a Timney trigger and a boyds stock. Less than 1" groups. He did a second to see if the first one was a fluke. Same results. Then he build a third, (cause he lives in TX, and both his grand daughters are Texas born and go shooting with him, so he figured why not have three) All three will shoot sub MOA
Im currently building a .243 for grandson. It will be his first deer rifle, it has a boys AT-1 stock (fully adjustable), PTG bottom metal so it takes AI mags, so as the Timny trigger shows up I will take it to range, but I expect sub MOA with it
You'll spend $300 - 400 on light barrel ($400 to $500 on heavy barrel) on sale. Plan on adding $250 for stock and trigger, and you should have a real shooter.