If you have a 2" focuser look at
http://www.televue.com/engine/TV3_Pa...n=Advice&id=96
If you have 1.25" only then 24mm Panoptic for maximum true field and 13mm Nagler for close-ups on DSO's. Add a 7mm Nagler for close-ups on planetary nebulae and planets too.
Note the above is a premium wide apparent field set that will last you a lifetime. You could stick with 50deg AFOV Plossls and for the cost of two of the above you could get all the Tele Vue Plossls up to 32mm which would be a very nice premium 50deg AFOV set. The wider AFOV is nice if you have an untracked DOB.
If you want one eyepiece to give you that wow factor go for the 13 or 12mm Nagler as your first premium wide field eyepiece. I personally prefer the 12mm but the 13mm is very nice and much smaller.