Hmm, 75 kg does not convert in 200lb (or vs) something is off here. Nevertheless either one should be good enough for a Hobie 14.
A short righting line (or system) will give you a lot of trouble. There are a good variety of ways to attach the righting line (or system). A very simple way to do the trick is to tie a line to the dolphin striker (if your hobie has one) or to the x-bar. During a capsize you throw the line over the hull in the air. The line should be long enough to place your body in a way that you get the greatest possible force pulling downwards. If you wear a harness it it might help to be able to hook your harness to the line. If you sail without a trap it might help to place a couple of knots in the line to make it easier to hold on to it.
Patrick