Yep, that's GW for you.
You'll have several days of easy mode runs. Then one day, POW!! You end up with a zeta'd level 85 Empire team.
I'm level 78 now and I'm hitting a lot of gear 10+ well developed teams, usually around node 9-10 in my case. Node 12 is usually fairly easy if I make it past that. Usually 85 teams too.
Had real trouble with a nihilus led sith team last night for example. Took two not very good teams to blow all their cooldowns before Phoenix could dent it, in fact it still took a few more goes to get a favourable RNG. Phoenix is a solid team as they self heal so you can keep them going all the way through.
Apparently it used to be much harder to get through.
So yeah, make sure you have a solid team for pinch hitting around or at least some sacrificial lambs. it gets worse before it gets better. Make sure your top 5 is all one team around the same level and gear, makes a difference.