I reckon the best thing you could buy is a coma corrector...unless you have one already. As a Refractor user I like stars to bre pinpoint allthe way to the edge and found in my 10" f4.8 anything over 50º AFOV was really disapointing..eg 100º ES 20 half the field was a mash of coma. Are the Ethos any different??? I doubt it.
After I bought and learnt how to use the ESHR coma corrector it was wow... I never knew Newt's could be so good! I still love my Refractor thgough
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What I use...wide views ES 34 68º flat field no abberations I can see, no secondary shadow. The 28mm 68º is the same.
ES 18 82º...wow what an eyepiece
Below that for the best I have had... Pentax XW 10mm 7 and 5mm....fantastic, only beaten by binoviewers, for me, which is an other experience.
So buy a coma corrector spend big on short FL eyepieces and less on longer FL ones.
As Tony said, you have to try some of these things...the difference between ES 11mm 82º and Pentax XW 10mm is a few more stars and better Planet views in the XW...is it worth it?????You need to decide. FWIW I found it took me 6 months with an eyepiece before it was keep or sell.
Matt