As a SEE owner after the nerfs of non-GL counters and buffs to some other GLs, I feel questionable about SEE's status as a GL. First of all he hits pretty weak on basic and even after his ultimate hi...
I haven't lost to a Rey team with SEE in a long time.
If you want a good arena team then you have to put forth effort and resources into it.
You mention the new fleet meta and a possible new arena meta. That is just what happens. So you either need to abandon SEE and go for JMK and LV or just try to build the best SEE team you can to try and counter them. The game always moves forward. You can choose to move forward with it or get left behind.