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One thing to keep in mind when selecting a low powered eyepiece for a telescope is the exit pupil of the eyepiece for the telescope. Just talking about the 8" scope, generally speaking, the lowest magnification you might want to go to is about 3.5x per inch of aperture. That should keep the exit pupil of the eyepiece below 7mm (about the maximum size that your pupil will dilate to when dark adapted).
If the exit pupil of the eyepiece is much larger than 7mm, you will begin to see the dark spot in the middle of the image caused by the obstruction of the secondary mirror (for newts only).
A 32mm plossl on an 8" f/6 dob will give you a magnification of about 38x and an exit pupil of 5.4mm, so it should work out quite well. A 40mm plossl would be about borderline for your telescope.
If you can afford it, you might want to try to get a televue panoptic eyepiece, which has a wider field of view. However, a 27mm panoptic (as an example) has a 2" only barrel so your focuser would have to be a 2" as well.
Best of luck with your spending spree. Buying eyepieces is a lot of fun. I had a set of Lanthanum eyepieces a long time ago which I thought were excellent too (same FOV as a plossl, but longer eye relief). The only reason that I sold them was to start getting my naglers.
Please post back with what you ended up buying Wade.
Dean
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