I have many ways I can cut grass, MMM, 3pt bush-hog, Zero turn, Finish mower with it's own engine, and my Power-Track 1445 could power a hyd mower if I had one. The one that I use the most is the Zero turn Dixie Chopper.
If you want to do flat land lawn mowing, there is nothing better than a Zero turn mower. I have several Dixie Choppers with 25 HP Kohler engines. Not only will they cut grass, but you can add a vacuum bagger for leaves and grass, you can pull the trash cart to the road, You can spray round up and throw out fertilizer. They are easy to maneuver and some are very fast. Some people say why is he cutting so fast, because he can. They are fairly easy to fix. They will cut hills, but you have to learn how. I slid down one hill in 15 years. With a set of gator blades and a bagger, you have one fine machine. Even women like using it.
You can get some good commercial used zero turn mowers about a third off new price.