(this suggestion is experimental, im not having positive or negative thoughts on it) Name: Surface Description: Infinite Health. There is a line going through whole map placed somewhere under surface. When a tank will touch or get under the line, it dies. The point is to dig enemies under the line and to not cross it by yourself. Track upgrade is a major thing here, but only half of maximum track upgrade functions on this mode, meaning if you have more than half of it you'll only have half of it working. In lobby there is an option called "High-Explosion Wep" (On/Off) which is On as default. If you'll turn it off, high explosion-radius weapons like Nuke will not appear which are too powerful for this mode. There is also an option called "Line Depth" (Small/Medium/High) which tells around where the line will spawn. Icon: Match Preview: (Idea might need some improving or additional features)
Idea is good but nobody will play it. It's good that you can set stuff like Nukes to off but there are plenty of other weapons with small explosion radius that can obliterate the map, like the sunflower thing and pyrotechnics. You can set them to be off as well I guess but then it won't be fun/the game will last too long. Game modes that force you to play with x type of weapons are not going to be popular.