This is probably not something you want to hear, but oh well. You said it's your first season with your own stuff and 2nd season ever, and you don't hit the park and you're in Ontario. Now forgive me if this is wrong but my impression of ski resorts near Ontario is that they're generally small with no steepness and less than 1000 feet of vertical (~304 meters). I'm in NJ, and I board in PA, which has similar mountains. I'm in Vermont right now, and the double blacks there are like blues here. Now I expected Vermont to be steeper alright, but I didn't think it would be that big of a difference.
I figure you're still trying to find out your riding style. Whether it be huge backcountry hiking, pow, just cruising, or serious park, it's probably not very apparent yet. When I started I had absolutely no interest in park whatsoever. Now the park is very appealing to me because it's fun every time, and you can switch up your tricks every run, pick different features to hit. If you're on a mountain where you can go through every run in less than 2 hours, it will get boring after awhile. The park is moar specialer, if you get what I mean
Damn that was one hell of a tangent. In a nutshell I think you should wait a year because the park pickle is a great board and I don't think you need to upgrade. If you can get the rider's choice at a great price, then get it. 154.5 will be a bit bigger, a bit more stable for freeriding but a bit tougher to spin and mess around in in the park.