For Saturn? You won't need 2" eyepieces. In planetary, high-power focal lengths there is no advantage provided by the 2" format. In fact, I believe a c11 is actually optimized for spherical aberration correction with the 1.25 vb and a prism diagonal. That's definitely the case with the c8. And with a scope with tracking, I actually prefer narrower apparent fields for planetary.
Where 2" eyepieces shine are in the longer focal lengths. You want something to max out your true field of view, something to give you a max usable exit pupil (max brightness for use with a nebula filter), and then one or two options to bridge the gap between your longest and brightest and your 1.25" eyepieces.
For max brightness, a 55-56mm plossl is the obvious choice. Televue if you want the best. Meade if you want a bargain. Russell Optics may also be worth considering.
Now a 55mm plossls also maxes out your tfov, but you will probably want something with more magnification and a wider apparent field of view. The question is how wide and how much do you want to spend?
You have the 68-70 degree class of eyepieces. The orion q70 / agena swa eyepieces are the value play. At f/10, I find them acceptable. The 40mm gives you max true field and is bright enough that you could skip the 55mm plossl. And if you want better performance, the Explorer Scientific 68 40mm is an option. And if you -want even better, there is the Telescope Vue panoptic 41mm. If you decide you want the 68-degree class of eyepieces, the 24mm ES 68 (in 1.25") is also a great option to have (or the TV 24mm Panoptic if you have the funds). So you may want to fill in that the gap between 24mm and 40-ish with something around 32mm. Oh, and if you choose the budget route, I'd still opt for the 24mm ES 68 over the 26mm Q70/SWA (I happen to own both).
The next step wider is the 82 degree afov. Here you will look at 30-32mm eyepieceso to max out your view. The standard in the TV nagler 31mm. The ES 82 30mm is a more affordable option with still excellent performance. The celestron luminos 31mm is the bargain contender (still over $200, though). If you go the 82 route, you'll probably also want something in the low 20s or high teens to complement it.
There are 100-degree options now too.
It is also worth noting that the F/6.3 Reduce corrector with a 24mm 68 yields an almost identical field to a 40-41mm 68-degree AFOV eyepiece, and does so at less cost and weight (plus you get the 24mm to use without the R/C). The same is true with a 32mm plossl and the RC in comparison to the 55-56mm plossl. A 2" diagonal is not necessary to get the most out of your SCT, if you are willing to put up with the hassle of taking the RC off and putting back on. On a C8 or smaller, I probably would not bother with 2" eyepieces if I didn't have another scope to use them on. On a C11, with a full 2" baffle tube, I can see going the 2" route though, but the bargain approach would still be with the R/C.
As far as filters, the general consensus is the first filter to buy is a true UHC filter first (Lumicon UHC, Orion Ultrablock, or DGM NBP) , and then an OIII.
Edited by jallbery, 06 May 2017 - 10:53 AM.