I am! I'm currently working on a remake of Strade's path from the original BTD. It will be very different though- lots of upgrades. If you wanna see more info about it, you can check out my personal website www.dirtymurdergames.com :D
Yes, I plan to put up the new game on Steam :) I don't really plan for an 'early access' phase though. I prefer the old fashioned way of going through proper beta testing in semi-private and then releasing a complete game. You can find details about my progress on the game at my personal website: https://www.dirtymurdergames.com/pgs/ykmetstrade.php I update that page every friday to keep the progress noted on it up to date :D