Drill ARE NOT an issue, and are extremely easy to counter. The only issue with the Drills, is the skill issue of people who don't want to actually waste effort to counter them.

I keep seing people saying stuff like "The game is going to turn into drill ping-pong! Drills are overpowered!". You know what you can do with drills? Destroy them. They're 1 kilometer tall and have HP of a potato.

You can just take a Kodiak, RPG and some rounds, and just destroy it from afar with basically no risk to yourself or any real counter. You can mortar them. You can use the Rocket Little Bird. You can use the Artillery Tank. You can use the regular Tank. You can use Havoc. You can throw C4 from the outside. There's a billion different ways to destroy them.

Drills are only allowed to stay because people just ignore them. It's not a balancing issue, or game design issue, but purely a skill issue.