The problem I always run into when considering the new skill is that something I think up as a new skill could always fit under an existing skill. I don't think it would be a stretch to say that Jagex has pretty much exhausted most skill ideas at this point. Right now, they'd either have to 1)make up something fictional like magic or summoning or 2) look very hard for something they or I might have overlooked. The real test behind considering new skills is whether it can already fit under a current skill. For example, when I first considered construction, I thought it was something that went under the crafting skill. Although this could be true, Jagex made the skill anyway with plenty of different things to use and ways to train than crafting. Anyways, if I had to take a stab in the dark at what the new skill might be, I couldn't say for sure. But, from looking at some of the occupations on a medieval site, I came up with a few possibilities.
-Gravedigging Skill
-Musician Skill
-Engraving Skill
-Jester Skill
-Sailing Skill
-Astrology Skill
-Spy Skill
-Healer/Physician Skill
That's the best I got. I bet the new one has to be related to one of them for sure.
