New HVAC

It’s that dreaded time where we have to replace our HVAC system. We live in a single story 2,233 sq ft home and currently have a 1 stage 3 ton Carrier. We were told that a 3 ton is not adequate for our home and need a 3.5/4 ton which kinda makes sense as our system currently is always struggling. I heard the best hvac for SWFL is a variable. These are our quotes for a 4 ton variable. One company said I would need to replace my ductwork if I go with the 4 ton 2 stage (cheaper) since my duct work was made to handle a 3 ton. If I go with a variable I wouldn’t have to replace the duct work. He also said if I went with a 2 stage it will always be humid in the house. Second guy said if I went with 2 stage my current ductwork is fine. I know stuff is expensive but damn was not expecting 19 k Thoughts ?