[JJ (Jason)]

OK, so I'm a newbie and proud new owner of a 10-inch Dob from BinTel.
It came with a 2-inch 26mm wide-view eyepiece plus 15mm and 9mm 1.25-inch Plossls.
I want to add a high quality eyepiece to the kit with extra magnification.
I'm looking at a 5mm Nagler or a 6mm Ethos.

I've done as much research as I can. The magnification with the 5mm Nagler will be 250x versus 208x for the 6mm Ethos. I think I'd like to go for the higher magnification of the 5mm Nagler, despite the lesser AFOV. However, my research has me wondering if this will push the limits of the scope (too much magnification) for the given conditions (light pollution) of my location.

Factors to consider:
- The scope is 250mm x 1250mm (F5).
- Most viewing will be from my backyard in the Chelsea area (Melbourne metro).
- I'm in my late forties and, although I wear glasses for night-time driving, I don't need glasses when using the scope (eye-relief shouldn't be a big factor at present).
- I mainly want the extra magnification for better planetary views.

What NOT to consider:
Price. This is not a 'better value' question. This is a quality and viewing-pleasure question. I don't care if the eyepiece ends up costing as much as the scope itself!

Considering all of the above, am I too concerned?
Is there any real reason NOT to choose either? (If so, what other EP may be more practicable?)
Could I even consider more magnification? (e.g. a 3.7mm or 4.7mm Ethos SX with even greater AFOV.)

I humbly bow before those of greater experience and wisdom - which is anybody really!

Jason.