Can I put custom utlities in WinPE?

I have various utilities on my systems, several of which come with bootable CDs for those times when the OS isn't available. The problem is that most of them use FreeDOS or similar to run the boot CDs when I have RAID 0 SSD for my OS - consequence, the utility discs can't my OS environment.

I was wondering if there was a straight forward tutorial somewhere which could tell me how (or if) I can build a custom WinPE environment that includes windows versions of the utilities I'm after (which I would put on a thumb drive). Then I could boot off this WinPE and run the utilities as required. The WinPE I'm thinking of using is for Win 8.1 64 bit.

This WinPE environment would also need the ability to load additional drivers on the fly. I say this because I use multiple systems with different drivers and I don't want to keep updating/creating WinPEs when new drivers come out. I know this is possible because the Symantec System Restore boot CD I have (which is based on WinPE) can do this.

I have different PCs using both legacy BIOS and UEFI boot configurations so I would be looking for something that would be able to support both.

Thank You