Re: smaller wildcat cals.
Since the 70's I have built and shot many, many wildcats. I currently have at least twenty five 22 cal and 6mm cal wildcats that were the best of all the ones I did. If I had to pick a few that fit your description in 22 cal it would be the 220 Weatherby rocket and the 22-250 AI. Those two are the fastest I have done that had extreme accuracy. The rocket is the first wildcat Roy Weatherby did and is all you can get blowing out a 220 swift. In 6mm the 243 AI is the best I have seen for accuracy and velocity. It has held numerous world records and wins in 1000 yard competition. It would be in the top five of all cartridges and calibers I have ever shot over the last 50 years. For the cool factor in 6mm the 240 Gibbs is a beast. I have two and they are incredibly fast and accurate. It is all you can get out of an '06 size case and will shoot 75 grain varmint bullets well over 4100 fps. I have one that is set up for 1000+ yards shooting and will hold .5-.75 moa to 1000 yards with the 107 smk over 3600 fps.
So to fit your description of cool factor that not many have that are some of the best out there those are my choices.
Predictions are difficult, especially when they involve the future