Wyowhisper- You mentioned that you want a 26 inch barrel as a max length. You can get some good velocities (energy) with that length from a 30 caliber but it will require a lot of case capacity and is going to kick like a mule, even in a varmint weight rifle. A muzzle brake
would help but I don't like wearing ear muffs in a hunting situation. A 300 Ultra, weatherby, Hart, or Dakota would all do very well, but strap on a helmet and a shoulder pad when you touch the trigger off. I guess I am not the burly, lumber jack type, cuz I hate shooting those large boomers. In fact, a guy I know that shoots competitively long range, had a 300 Ultra built for long range deer and it broke his front tooth out.
A 7mm Dakota or STW could deliver some impressive ballistics from a 26 inch barrel and to give you an idea of energy, if you launched a 160 grain VLD type bullet with a BC of .6 at 3100fps, you would have around 1100lbs. of energy at a thousand yards. Again though, pretty fierce recoil. A .280 Improved is a good choice and can deliver ballistics equivalent to the 7mm Rem magnum and is actually quite pleasant to shoot. I just had my 280 rechambered to the improved and really like it.
The 6.5's offer the advantage of very high bc bullets which retain velocity and deliver good energy to distant targets without requiring a bucket full of powder behind them. For example, with a 26 inch barrel chambered for 6.5-06 improved, launching a JLK match bullet with a BC of .645 at 3,050 fps, you have right around 1,000lbs. of energy at a thousand yards. If you went with a 6.5-300WSM, you get even more than that and it would still be pleasant to shoot.
Hope this helps.