Again, it depends on what kind of hunting/shooting you do. A .270 has way more range than the .30-30... in the hands of one who is familiar with the rifle, it is a legitimate 300-400yd rifle. It's a great caliber... possibly one of the BEST all around calibers for north American hunting, being perhaps slightly light for big elk and moose, but near perfect for everything else.
The 30-30 is limited to about 150yds, but is borderline perfect for deer sized game in that range.
There is nothing wrong with the Remington pumps, as long as you use good quality ammunition, or meticulous reloads. They are probably faster on the second shot than even the Marlin, if that matters to you.
Value-wise, is the pump new, or almost new? The condition of the rifle will determine whether it is a "good trade" or not. I imagine the Remingtons are more expensive new than the Marlin, but I haven't checked prices lately.
As much as I like leverguns (a LOT), I'd be tempted to go with the .270, for the versatility.... but that's just my opinion... worth what you paid for it.