You could look for a faster twist barrel for your Hawken and just swap them out when necessary.
Currently, I'm having great fun with my TC Firehawk. Unfortunately no longer in production, but the striker fired Knights are. Hard to find a striker fired that isn't accurate. They're legal everywhere and you can use the powder and caps you already have. Commonality of supplies is wonderful!
I've used a number of different inline designs and consider the striker fired designs to be the best. Of those, I consider the TC Thunderhawks and Firehawks to be the best of the bunch. No removable breechplug is fine by me. Personally, I think it was a solution in search of a problem. They can be found used for very reasonable prices, and are superb shooters.
Good fortune to ya