I don't think Shinkaruk's ready, personally-- He's had nice results, but could really use the time in Utica.
Jensen, I can give or take. He's obviously still got wrinkles and bad habits in his game, but he's absolutely physically ready for NHL play (in terms of tools-- Speed, strength, puck skills, instincts), and his weaknesses aren't horrible (many NHL caliber players have the same kinds of weaknesses-- his defensive game is actually getting better as well). I also doubt that putting him in the AHL will help him improve those weaknesses-- He strikes me as a guy who is just as likely to develop more bad habits down there against easier competition. Unless he's absolutely dynamite over the next few games, it's a numbers game for me with regards to Jensen-- If it's EASY to keep him up in the lineup and you don't have to trade anyone useful in order to do it, I'd like him on the team, if not, I don't mind sending him down. I wouldn't be so quick to trade Hansen/Burrows to fit him in right now, that's for sure.
Horvat I think should be on the team. His game is very refined, he looks physically ready, and you can tell that the instincts are there, he just needs to get comfortable. He also fits in perfectly with the team and fills holes that this team desperately needs. I can see him starting out as a solid past-his-prime-Pahlsson type player to start the season and get better as the season progresses (I'd expect him to not look much worse than Higgins/Hansen by that point). The junior thing has been said many times, and I agree. I see no reason not to keep him with the team. Even if he gets knocked down to the 4th line at some point (which I don't expect to happen, but it could), I would still prefer to have him in that spot playing with Richardson/Matthias/Hansen rather than in the OHL. In either case, 3rd or 4th line, I don't see it hurting his development, and I don't see him hurting the team. His wheels don't seem like much of an issue to me either.
I personally wouldn't have sent down Gaunce so early either-- he seemingly started to make the same kinds of strides that Horvat is making right now. Then again, I wouldn't have him make the team over Horvat (or in ADDITION to Horvat), so I guess it's moot.
Horvat > Jensen > Shinkaruk
In any other year, I'd give Shinkaruk 9 games just because he's earned it with two years of solid production, and you'd like to see that rewarded, though. To go two years putting up the preseason numbers he has and not get a sniff would be a bit of a shame. But I don't think he looks like a full time player.