Light-weight Inflatable
A dingy-davit system would be very nice to have but, as you pointed out, the weight on the stern has an adverse affect on sailing performance. Also, when the boat lists there can be a problem with the dingy wanting to shift. Also, there is the cost of the davits, a certain amount of lost convenience by having the stern area encumbered. After a number of years sailing I've gone from hard shell to inflatable. After trial and error I settled on an Avon 3.15 rollup - it planes with two people and an 8hp outboard, rows easily, and is very stable. An excellent dingy. However, I don't like to tow my dingy because of drag, safety (can flip in a wind), and inconvenience when comming up to a dock. The Avon with Hypalon fabric has been very durable, a real plus, but.... it is heavy. I keep it stowed amidship on the coach roof, folded in front of the dodger. To launch and retrive the 115 lbs is not the easiest, even with a bridal, using the main halyard, a 43 winch, and a block and tackle (preventer). Suggestion: for non-yachts without paid crew, go with a cheap, light-weight inflatable. They are much easier to deploy. Use either a small, lightweight outboard or just oars. Stow on the coachroof or inflated on the fordeck - but always keep lashed down to prevent it from going over the side. The fabric on the cheap units may not last as long but the ease of handling would be a blessing.