Two schools of thought.
(1) If you just intend to drive it "normally" then identify the things that need maintenance and replace with suitable factory parts.
(2) If you want to do DE/AX then look at upgrades.
From personal experience, some of what takes the longest time is cleaning/prep and sending stuff out. I sent my rear Bilsteins to Chuck at ER to be re-valved. That's 3-4 days there and then the same coming back (I'm on the east coast and he's on the west) plus the time for him to do the work. Cleaning up the spring plates is no fun at all. Then getting them re-plated adds more time. If you had everything brand new and all you had to do was R&R, you could easily do the rear in a weekend (not including the alignment). I haven't done the front yet but I'm told it's even easier. It also depends on how anal you are.
Anyway, I don't think the actual time spent turning a wrench is that bad. If you end up having to make a couple of trips to the auto parts store that can kill your productivity. The first time you change your oil is really slow. After the 3rd time you're a pro. The problem with suspension stuff is you may not do it again for 10 years and the first time you're learning so it is what it is. Cleaning and prep... That takes me the longest.
In my case my rear struts were gone. T-bars were fine and the spring plate bushings had more life in them. I just decided to upgrade the t-bars and go ahead and do the bushings in one go. The bushings were original -- with over 30+ years I was operating under the premise that time, not use, was eventually going to be my enemy.
The spring plate bushings becoming more oval is an indication that they need to be replaced. At least that is my understanding.