Check out my current expertise. According to my reforgelite and everything I can think of, that's as low as I can get my expertise in this gear. Is this the best I can do right now?
That looks pretty much like the best you can do with your expertise if you've reforged out of it on ever piece that has it. Most melee have really high hit and exp this tier and there is nothing we can do about it. Not necessarily a terrible thing btw. It has a lot to do with the Renataki's trinket.
What are good ways to know that you should use the glyph of fire ele totem or not? And suppose you don't have a ton of mechanics or crazy things happening at the moment, how do you fit your fire ele's immolate and/or anything else into your priority? Where does it fall?
Fight length. Given that my guild is on a few heroics right now, we really out gear the normal modes that we do now, making fights much shorter than what they were when we started. Maybe Chill can clarify to best gear lvl to use FET Glyph full time (as I started using it all the time around trhe 520-522 ilvl mark) but general rule is use the Glyph if you can cast it twice as much as without. IE: fights that take 6-8 minutes, your only going to be able to cast FET 3 times: ( at 0:00, 3:00, 6:00 = 90 seconds) and without the Glyph 2 times: (0:00, 5:00 = 120 seconds) meaning not using the Glyph would be more beneficial. Fights longer than 9 minutes, than the Glyph would be better.
Now given the gear lvl and my fight times, its pretty much straight up best for me to use the Glyph all the time, on every fight, even on heroics. (except for Dark Animus, I don't use the Glyph because honestly you're only going to use it in the final boss burn phase)
As for the Elemental itself, you should have its Immolation and Fire Nova toggled to auto cast... And if you're using the Earth Ele as well (which you should when using PE) you should toggle the Taunt off. This means on your Fire Ele, the Fire Blast will also be toggled off. Instead of clicking/bind the spell manually, a lot of us have found using macros for a few of your main spells to cast the Fire Blast is the best bet.