The new one uses a micro usb jack for power
...
I would tell them WTF did you shrink the power jack.

They've always used microUSB for power. Maybe you're thinking of another SBC? The Pi model B form factor is pretty popular, so I could understand some confusion.
I have had power issues feeding some rasp pi.
That is a legitimate issue with the 3. Depending on how hard you're pushing it, it can be touchy with power supplies, and you should pay attention to wire gauge in your power cables. I recommend at least 24 gauge, especially when overclocking.
the Pi is drawing power from the Terminus
I can't express how much I like this. I've done similar things in my Pi-powered projects, and it really helps in tidying things up.