Shortly: carryweight is needed for everything but fighting.
If, possible typical combat builds will always take small frame because they only need to carry their gear. They will also take only as much strength as their main combat weapon requires, even less if possible. Weapon handling is obvious choice so I'd say most builds never get more than 5 strength. That plus small frame is 45 cw which is hardly anything. Now that we got various anti-crit perks and traits, taking str6 for stonewall isn't that popular anymore.
However when you need to do anything else but fight, carryweight becomes very important.
I suggest increasing default carryweight up to 60 when having str1. In fallout 2 str1 + small frame equals 40cw. Why's it 18 in fonline?
What comes to small frame, it's like Fast Shot used to be for big guns except that it's for everyone (all ape-builds). People have just kept their mouths shut about it.