Hi Ben, the following is what I have found works really well on my 6" dob.
10mm, 15mm, 25mm, 30mm & 4mm (when seeing is good). The 10,15 & 30 are staggered in this range so when I barlow, I do not double up on focal lengths. I do not barlow my 30 - it's an ulta wide 80 deg ep that I only use (and is brilliant for) widefield scans. I find things in this lens, and then bring them in with higher mag. Most of my ep's now are widefield. I just find they work better with the dob, especially at high mag when you want to get a really good look at planets. I could never look at them long enough in my 10mm before I replaced with a 70 deg fov one. The smaller the fov, the more you have to work the dob- I could never get the planet long enough to give it a proper look. Now I have time to turn away, have a stretch, and even accidentally bump the dob, and oh hello.. it's still there
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For my 15mm, I have an Orion Expanse (66 deg fov) and I really love this ep, even compared to the Pentax, it performs really well. It's sharp and contrasty (just the edges suffer a bit, but I have a big field of view and for the price I don't really care), even barlowed I love it. It is in a totally different league compared to the standard ones that come with the scope (only $90). We our lucky with our focal length of 1200/F8, eyepieces for us are very forgiving and don't give us as much grief as faster scopes (most ep's will work well in our range).. well that's what i've been reading anyway each time I do research to buy an ep.
The U.O.'s have very small fov's about 45 deg, bare in mind you will be working the dob more than looking at the planet. Which is why I didn't go down that path. See if you can have a look through one so you can judge for yourself.
It is very easy to keep buying eyepieces until many dollars later you finally find what works for you. I made a point of not wasting money and did my research as thoroughly as I could. By getting good eyepieces and spending the dollars straight up, is a lot cheaper than buying a whole lot of useless eyepieces. I say, if you can afford it go Televue, Pentax or Vixen in your most used (which will most likely be the 10mm & 25mm). You won't be sorry. Nothing else beats these ep's as performers for very good reason. Even my barlow is a good quality one (ED) so it performs well with quality eps. The TMB's certainly do seem to get a good rap, but the fov was too small for me. Don't forget once you barlow that 10mm to bring it down to a 5mm, you will work that dob even harder (higher mag, less fov). I don't get anything under 60 fov anymore. For me, it just wasn't worth the work, unless you get really really good at nudging your dob.
