As others have said, a 60" deck might be overkill. I mow 7 properties totaling 5 acres every week with a 48" Gravely ZTHD... in under two hours start to finish. The smaller deck lets me go through gates and between obstacles that would block a bigger deck. It also follows the ground counters a bit better than a bigger deck, so there's less scalping and fewer high spots.
If you only have two acres, you're looking at an hour or less to mow it with any ZT machine. Since you mentioned that the ground is bumpy, I'd recommend getting something with a suspension seat, and putting that higher up on your list of priorities than the deck width. Your back will thank you for it.
Also consider required routine maintenance. Some mowers have a bunch of zerk fittings, and some can be difficult to reach. Not saying that's bad... grease is good if used adequately... but if it's not, well, you might be happier with a mower with sealed bearings. i know that I am.