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I had thought that the way for best ever planetary viewing would be via a 2" short FL EP.
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Unless you cannot use a 1.25" eyepiece, or dislike using the adapter, there is no point. For any planetary eyepiece the 1.25" eyepiece will not limit what you can see. Honest! See
here for the maths (see 2.2 and 2.3)
Maximum field stop in a 1.25" is about 27mm, and in a 2" about 48mm. You only need the latter with wide fields. Roughly, for 8"F6, the crossover point for 1.25" to 2" is about 32mm with AFOV of 50 degrees, or 16mm with AFOV of 100 degrees. So for say a 30mm 68 degree eyepiece you would need a 2" eyepiece.
So pick your poison - maybe somewhere in the 6mm range will be as far as you want to push it, a wide field will allow more time to watch it drift by.
regards