I have a house on a slab and the only thing I would have done differently would be to have built on a raised slab. Gives the same appearance as a house with a crawl space but I would not have to worry about old squeeky floors, fiberglass rat beds or damp moldy crawl spaces and with today’s plumbing I haven’t heard of a lot of leaky pipes with slab houses. I’m sure that’s a fear of a lot of people but my house I built new 22 yrs ago and not one issue with anything in the slab.