Like the good Dr above said - get the saddle position correct and then base the other stuff off that. Go for the fitting, now is actually a pretty good time as you've had a chance to try some different stuff and pedal around a bit. Old bobcat may have something about moving the saddle back a bit. Without actually being there (the videos are helpful) it's difficult to give more than just a suggestion.
IMO you are actually a little upright when out of the saddle and not far forward enough. I would find it hard to get a good sprint going in that position. But that's just me. Seated you look pretty good, but that's over the internet. Interestingly that very same position if just shifted rearward, all things remaining equal, would actually feel different as you would now be further behind the bottom bracket.
As far as ad/disadv of smaller/bigger frames. In the old days of steel bikes smaller usually meant stiffer and lighter, in the era of CF that's all moot. A larger frame may have you stretched out to far, a smaller frame could have you too low. Both can create physical discomfort on the bike. However with the various head/top tube lengths now available these are just generalizations.
"all in all it feels good but i dont really know what i am looking for and want to try and get a better idea of what i should be expecting before i make any changes" Maybe you've answered your own question, maybe just ride the bike for a bit and see how things go. Things (problems) that are there are easy to find. There will come a point where after all the suggestions only you know what feels good. After awhile it'll be like friends choosing your dates - there will be lot's of good intention, lot's of experience, lot's of opinion, but only you will know who you would be happy being trapped on that desert island with.
Another way to think about the smaller frame issue, is did these bike companies decide that folks under 5'3"-5'4" just weren't worth the effort for making another frame size. Maybe you are not tall, but you are certainly not the shortest. I find it hard to believe that at 5'5 you would be riding one of the planets largest manufactures smallest offering. People do devaite from "average" proportion, but you don't look excessively outside that range from the pics/vid. We do need to get something that fits right but from what you have told us (there maybe more), you may have the same issues getting comfortable on the smaller size. Case in point - I am 5'9", average build. I have succesfully ridden sizes 52-56cm. The 56cm was waay to big (it was my first bike as a teenager) but with a short stem it worked out ok and I took second place at Bear Mountain on it. The 52 had a long stem and had me low, a little too low but I was a young flexible guy and dealt with it. It turns out mama bear at 54 is just right although I was able to get a "similar" position on all the other frame sizes. IMO you are in the realm where minor tweaks or component changes will save the day. Not the smaller frame. I'm just some loon on the intinet viewing through the lens of my low-res monitor.
A lot of this stuff is trial and error. Most giving advice here have run through a few different bikes and a different position evolutions. Getting this perfect out the gate, although possible, is unlikely. Sometimes our positions are such because we've ridden ourselves into them. In my case starting on larger frame sizes, despite being pretty flexible, am not a huge fan of short head tubes. One day down the road you may be giving us advice on how to setup.