If you like 150 skis, you may want to try skiboards - I normally ski 170-180 length skis (and I'm 155 lbs), but I occasionally use Summit Marauder (125cm long, 117mm wide under foot) for goofing around. As long as I don't go too fast, Marauder can handle pretty much any condition.
Eventually you want longer skis if you want to ski real steeps, or ski at high speed, or ski really deep powder. But if you don't care about those, shorter skiboards work just fine.
That said, using shorter skis as a way to get over plateau sounds like a suboptimal way to me. You can't easily learn and practice some of the skills necessary to overcome the plateau with extremely short skis.