I don't use the metering in PT as anything more than a sanity check. Always use a metering plugin. PSP Triple meter is a good one as is the one from Brainworx called bx-meter - see here:
https://www.plugin-alliance.com/en/p.../bx_meter.html
I like the latter because it has the Katz metering system as part of it. A third one I sometimes use is DP Meter Pro from Blue Cat.
As to what level you use that is entirely up to you. I suggest reading up on the Katz metering system to get a good idea of what to look for; you'll find with that that what you're looking for in metering levels depends on the genre of music in play.