who doesn't let someone in their party/raid because of simple mode? that's the same as not letting somebody in because they macro, which is just stupid (if this is the case, WLs would never be able to get in any groups). I can see a group not allowing someone in because of a lack of DPS (apparently in the case of TC) or inability to do mechs, but nobody actually cares whether someone uses simple mode or macro. to get back to the topic at hand, if TC is pinging 180 normally but up to 300 during encounters, I would question whether or not optimized graphics settings are being used? bns ping takes into account everything, including fps, instead of just the relay time, so if you're experiencing that big of a gap in ping, is your fps also dropping drastically?
you can also try macro-ing and test out different intervals for flicker. while nothing will beat manually cancelling with full concentration, it's not always easiest depending on the content you're doing. I ping normally at about 130-140 and it goes up to 180-190 during encounters, and I found 650ms in between flickers to be a decent spot (the macro is literally just LMB), so I just hold F and macro if I'm using it.