Smaller boat = more sailing time.
Yeah I'm not sure I share that philosophy. My boat takes no longer to prepare for a sail than a small boat. I often have 26ft'rs getting to their boats at the same time as me and I'm long gone by the time they have got through bending on sails, stowing cold boxes, etc. I unzip the stac-pac, switch on the fridge, flick the start key and dump the mooring and I'm outta there.
My boat is always in a good condition but it is after all, a tool that I use for my enjoyment. In much the same way as my car has a finite life and suffers from bumps and scratches, so too does the boat. And if I were to run myself ragged about every glass of red wine that is spilled, every scratch that happens, every dent in the cabin sole because a plate was dropped, then it's time to get rid of the thing.
Everything should always work and the critical things should be as reliable as they can and due care will be taken to look after her but the boat was only new once - it'll never be new again. No matter how much you spit-n-polish, time will reduce the value and a shiny 30-year-old is not going to be worth a vast amount more than a well-used 30-year-old. The effort and cost to keep it shiny isn't worth it (unless that's your passion).
As far as costs go, I guess if you want a show-piece you're possibly right. Sure, a bigger boat costs more to maintain but that's because it has more things that can fail so it needs more maintenance, but it's also because all the stuff just costs more. The standard of living that you are prepared to put up while sailing with will govern this. I like to live on my boat like I live at home and I'm prepared to pay for it.