A 270 and 30-06 are so close in performance they are pretty much used on the same class of animals and are better suited forantelope to moose rather than varmints to antelope.
I will be looking for something that I can shoot anything from coyote’s up to antelope and do a little more long range hunting and target shooting.
I think a .243 would be too small for much of the uses I want
Why do you think that the .243 is too small for antelope?
For animalsin the varmint class to antelope and deer a .243 Winchesteris as perfect of a cartridge for this job as there is.