Thank you so much for your feedback! Yeah, when both players lose their drifters it very easily ends in a stalemate.
There are a few solutions I have been considering. The first thing I want to get rid of is the enemy teleporting/map looping. Of course, there would need to be an out of bounds area on the sides as well but I would make the play area a whole lot larger so the size doesn't feel to small.
That doesn't exactly directly address this issue, but this next idea might. I have been thinking about a surrender system, not only for enemies but for the player as well. Enemies might surrender when you are completely annihilating them or when maybe they have lost all horizontal or vertical thrust. The player would also have the option to surrender, though it would be more likely a "tactical retreat". They wouldn't lose a life but maybe they would lose some money and the player wouldn't advance and have to retry the enemy again.
Another change that might help is with weapon range. I have been thinking of removing the range for a damage drop-off system instead. That way if it ever comes down to only vertical thrust, you can still poke each other.
I could also make the warp core start with some vertical and horizontal thrust. Another simple solution would be to make a small game rule where you lose if you no longer have drifters (like the floatron rule).
While not all of these solutions will be implemented immediately in the next upcoming update, I will make sure to do my best and fix this infinite nothing gameplay. Thanks once again for this feedback! It really helps during these early stages of development.