OGRE is the first game published by Steve Jackson. If you're not familiar with his name, he's the publisher of the Munchkin card games. OGRE is now 40 years old, and still a good game. Yes, it is a two player war game, using turns and a combat results table. It's dated, but still a gem.
I am a proud Grognard. I simply cannot leave rules sets alone. So, here are my favorite house rules for OGRE.
A GEV class vehicle over open water which receives a "Disable" combat result is destroyed instead. It sinks to the bottom when the fans stop running.
That's it, really. OGRE is nearly perfect as-is.
That being said, I do have my own set of rules for playing OGRE with unit qualities. Each side has a quality - Untrained (1), Green (2), Seasoned (3), Veteran (4), Elite (5). Ogres don't have unit quality, as they are practically perfect in every way as they are.
Unit quality comes into play when a unit is disabled. A disabled unit which takes a further 'disable' combat result makes a quality check. If it passes, it survives. If it fails, it is destroyed as normal.
Unit quality also comes into play for recovering Disabled units. Instead of recovering at the beginning of the second turn after being disabled, they make a quality check at the end of each of their own turns. If they pass, they recover. If they fail, they remain disabled.
Unit quality also applies to disabling checks for GEVs in woods, for vehicles getting stuck in a swamp, and for recovering from being stuck.
Unity quality also applies in overrun combat. The unit with the higher morale shoots first, with defenders winning ties.
If you want to make Ogres even deadlier, more like the Bolos they are inspired by, simply have them fire in the enemy's combat phase. Defending Ogres should fire first, of course.