2018 MBP 1 Hour Battery Life & Other Issues

I have a month old 2018 MBP (2.6 GHz Intel Core i7 w/ 32GB ram) and have had nothing but issues with this computer. I upgraded from a 2013 MBP, that had none of these problems at all.

My biggest issue is battery life. My battery lasts from 1.1 to 2.5 hours and that's it - only running firefox, photoshop, and coda. Dropbox is running in the background, but if I quit it, it doesn't really seem to make much of a difference. screen brightness is usually at 50% or lower. I also have issues with it constantly locking up while sleeping, so when I go to wake it up (both with monitors attached and without), I have to hold the power button to force wake it. It also seems to have some issues with corrupting my backup drive (same one I used with my 2013 with no problems).

I took it to the apple store today and it passed all the hardware tests, so they thought it could be from some kind of corrupted files during migration assistant. So we wiped the computer and upgrade to Mojave. 2 hours and 40 minutes from a 100% charge, I'm already down to 9% so obviously it didn't help (I have been transferring files from my TM backup and installing apps and setting up prefs and thats it).

I was hoping someone would have advice here - everywhere I read seems to have the MBP battery life at 4-6 hours *minimum* and people are reporting 8-12 hours doing a lot more heavy work and using a lot more apps than I am. I'm not doing video editing or 3-D graphics stuff, just basic coding and viewing PSD files and such. The only option left apparently is to send it in for a week and hope they can find what it is and fix it. Of course, this is the only computer I have so I can't work or get paid without it, and it would suck to have to set it up for the 5th time (migration assistant failed several times when AI first got it and now I'm manually setting it up as per apple's advice). I've spent more time trying to get this computer just working the same as my old 2013 and it's frustrating as ****. I honestly regret selling my 2013 MBP and Thunderbolt monitor, this new system has been nothing but stress (don't get me started on issues of plugging hds into the LG monitor hub >_<)