My three-way head for the smaller tripod is a Manfrotto 460 MG. It doesn't have the levers but more comfortable rubber knobs. I don't know whether that would be enough for medium format but in my experience is OK for the small format. I bought it second-hand on an auction site and I am very glad I did.

I mount it on some Slik legs which I bought in 1989 for birdwatching, therefore it had a two-way head with one lever, good for telescopes but not good for photography.

I long pondered whether to substitute the legs but, as said, the biggest concern was the cost of theft/forgetting/damage in the trunk of the car etc.

Don't analyse too much. A tripod always has its use. If you buy some cheaper legs and you find out that they are not good enough for the Hasselblad, you will still have some cheap legs for situations when you don't have an Hasselblad but you need cheap legs. Think airports for instance.