Bob and Paula,
I know many have been happy with the small window A/C units, and that is fine if that is what you want.
I have tried several of the portable "roll around" type A/C units and I prefer them. They usually have dehumidifying settings which really gets you back into a sweet, dry interior after sitting at the dock a long time.
The BtU ratings can be a bit misleading. I had a single hose vented 11,000 BtU unit that did not evaporate the condensate water well at all, so it had to be drained with a hose off and on, or the tank emptied.
When that unit failed, I found a De Longhi 9,000 BtU unit with DUAL VENT HOSES - one drawing outside air in and the other exhausting hot air off the coils and as such carrying off the condensate water without a hitch.
The 9,000 BtU De Longhi cools much better than the 11,000 BtU single hosed unit which had to draw outside air into the cabin thru a cracked window, etc., to work. That kept the hot, moist outside air coming into the cabin.
Right now many of these units are on sale at the discount stores and they are smaller than ever. I keep mine in place with the black rubber bungee cords, so it is easily moved or removed. The C-Dory 22 could probably get by easily with a 5-7,000 BtU unit.
Also, these units often have HEPA filters built in, which should help your wife's condition.
Whatever works well for you!
John