That's a pretty wide range in terms of boat size - particularly when you start looking at moorage and maintenance costs... seems to me you need to narrow down your ability to keep up with whichever boat you ultimately go for.
Pearsons have a pretty good rep and a strong support base here on Sailnet, the S2 is likely to give you better performance, and may be the better choice for predominantly shorthanded daysailing. The Morgan, older, smaller, will likely be more manageable esp when docking.
The larger Columbia and Islander are putting you into a different sphere altogether, and they don't jive with the rest of your list, really. If you're looking at boats that size, then your list of options will be bigger too.
If your list is based on price point, then the larger boats at lower values tend to mean more problems.
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)
1984 Fast/Nicholson 345 "FastForward"