I used to use a Mk2 tent with plastic hoops to hold it in shape – it was made of PVC though and very difficult to seal the seams. I now have a nice simple Mk 1, although I reckon that a single hoop from rowlock hole to rowlock hole would justify it’s existence by the extra room it gave. I have also seen ralph Roberts Mk 2 tent. His is held in place by sail batten that passes through slots in his gunwale and then into small pockets in the hem of the tent. Locks the tent to the boat nively.
To be honest I am perfectly happy with my Mk 1 as most of the time I only have the front half up for wind protection and all the living is in the open at the back of the cockpit (even sleeping).
Your idea of a rope bridle is the best attachment method – most tents have velcro strips that pass under the bridle to fix the tent. This is very easy and quick – I can get my tent up in three minutes.