maxed out every single PP upgrade and runner upgrade, and no. their movement speed is still abysmally slow, they still take forever to fill their capacity (it seems like youre ADDING time the more things they carry, which results in them gathering so slowly at ~10 units that they are almost garunteed to get hit by something), and i STILL cant even collect 1% of the resources i generate.
this will NOT be fixed by adding a "bulldozer". ALL that will do is act as an alternate unit you EVENTUALLY get. focus on making the runners actually useful, before you bother making other resource collectors. either that, or MASSIVELY drop the prices of everything related to the runners. id say an entire order of magnitude, as the ridiculous exponential cost increases, as ALWAYS, far outpaces your ability to actually generate resources.
also you really need to turn the calamities down a few notches. 90% of my playtime the screen is just covered in falling rocks and exploding shit stunlocking all my guys, and the literal only way to allieviate that (because several artifacts increase corruption, and you literally require them to progress eventually) is by pretty much ignoring all my mining units and generating virtually no resources in the first place.