The Ultima 30mm is a great eyepiece, possibly the best 30mm plossl design around, unless Clave (French plossls) make a 30mm, oh and the Takahashi 30mm is possibly a little better. The Ultima 30mm is the same eyepiece as the Parks 30mm (oops! in my opinion that is) and probably the same eyepiece as the Orion Ultrascopic. I have found the 30mm Ultima to be slightly superior to the TV plossl (of a similar focal length) for planetary contrast, and a lot better than the Meade Series 4000 32mm.
The other TV eyepieces you mention are all fine. Is the Skyquest 8" an f/6 Newt? If so consider the TV 12mm Type 4 Nagler. At 100x you'll get some impressive views of globulars and planetary nebulars.
Consider also the Powermates from TV. I have a 2" 4x and it provides high contrast images at powers around 500-600x with my 308 f/6 Newt.
When it comes to whether expensive eyepieces are worth it or not - some are some are not. The really high quality eyepieces (those made by the Germans for individual telecope matching a long time ago) are not available to us mere mortals. Remember that an aftermarket eyepiece does not correct for individual telescope abberations and hence can not improve an image, only deteriorate the image less than other eyepieces. Once the image has formed.....the image has formed. Japanese orthoscopics are generally quite good, The Zeiss Abbe versions slightly better (if you can find any secondhand). Pentax orthos. are also reportedly very good. What you have suggested seems fine, but consider a Powermate, else check out the Astro-Physics 2" barlow.