Both excellent calibers for a Contender, and both, in my opinion, excellent deer and smaller game killers. I like the idea of the 7-30, a bit faster and more unique of a caliber than the 30-30. Reloading for each should require about the same amount of time and effort, as mentioned before, forming 7-30 brass from 30-30 is easy and fast.
I am a big fan of the 14" barrel, and both calibers are easily manageable in this configuration. I, personally, do not like the muzzle brakes on these barrels. I have a .375 Win. Bull barrel, and recoil is manageable. I do not like the large amount of muzzle blast and the ear-thumping noise made from a muzzle brake. Again, in my opinion, you can handle the recoil, lessen the noise, and shoot just as well with a bull barrel.