If you have no 1/2” drive, get yourself a set of shallow, chrome to start with.
If you’re not used to using 1/2” drive, you won’t believe how useful they are, or how nice they are to use. Despite the advantages of 3/8 drive in some circumstances, I use my 1/2” drive pretty much every day.
Get a generous overlap of sizes with your 3/8 drive. Even if you’re using a relatively small size, 1/2” drive makes all the difference working on over tightened or corroded bolts.
If you can run to them, get a regular length ratchet, a long ratchet, a breaker bar of at least 2’, and extensions that don’t twist!
Add deep sizes as you need them. I don’t think I’ve ever needed a deep socket above about 7/8”, although I do own a few.
If you have a 1/2” impact wrench, get impact sockets for it. Treat then as a consumable.
If you get chrome sockets, they will last a lifetime if used correctly. I‘m still using good quality sockets bought by my Grandfather in the 1930’s. He said they were expensive at the time, but don’t seem so bad 80 years later..!
Don’t get too hung up about sets without skips. Above about 19mm for example, there are many sizes not used by any standard, so instead of buying those, perhaps buy a couple of bigger sockets that you might use.
Do consider used. The bigger sockets don’t wear like the smaller ones, but cost more new, so can be a great buy used.
Do consider just buying what you need. The big sets from reputable makers are costly, often contain things you won’t need, but omit things you might (such as Torx bits)
Personally, I have sockets up to 32mm, 1 1/4 SAE and 1” Whitworth. I have hex bits up to 19mm and 3/4”, Torx bits up to T60, square sockets up to 1 inch, and I’ve needed ALL of them at some point - thankfully not on the same job..!