What I wanted was a character that can solo moderately effectively, and be able to have group utility as well. On first blush, a Theurgist seems to fit the bill, and as it turns out, I guessed correctly.

The question remained though, how to spec it? There are a variety of end-game specs available, and most of the articles here seem to only talk about that. But I am one of the few idiots who actually LIKE PvE, so I was interested in the progression on how to get there as much as the destination.

Here's my story by character level...

1-18: ice. 100% nukes, max level pet. Soloing, especially spirit weak mobs, is almost too easy. End with ice:18

19-32: earth. At 19, you get self bladeturn. At 21 you get friend bladeturn. At 25 you get usable earth pet (for variety, or whatever; I rarely use them solo). At 26 you get group bladeturn (not as good as PBT, but works in a pinch.) At 32, you get 10 sec PBT. End with ice:18, earth:26.

33-39: ice. Basically shoring up your ice spec to help with nukes. You'll probably be grouping in this range a fair bit, now that you have PBT. Your nuke will be necessary since most groups will be taking on things your max-con blue pets rarely hit. End with ice:28 earth:26.

40: respec ice to 35 earth, rest ice. You end up with ice:19 earth:35. You now have the 8 sec PBT, and ice pets that are still max-con for your level. Note that you could skip the previous section and just keep ice at 18 and dump points into earth from 32-40, but your nukes would suffer, for no real gain. There's nothing in the earth spec line from spec 26 to 34 that is really exciting, or necessary for solo OR group.

40.5-50: ice. When you hit 40 you'll have 19 ice, which gives a max level 37 castable pet. Using the "pet is 7/8 your level" formula, the level 37 castable pet will be ok for up to character level 42. Using the miniding points, when you hit 42.5 you'll get the next level ice pet (25, max level 50) which can last you through character level 50. End with: ice:41 earth:35.

This may not be the best progression/spec, or even good. But it worked for me. It did what I was looking for:
* Group utility: Damage Add, haste, speed, penultimate PBT
* Soloability: Throughout the entire level range; no "dead spots"

You dont really need to invest more than 25 ice, it is enough for solo, you will be using ice pets and not nukes. You also dont need more than 25 ice for rvr since u will not really be nuking , and 25 lvl ice pets are adequate. Something along the line of 45e/29i/left over to air is the best for rvr. 45 earth will give you 6sec pbt, and 40 lvl earth pets which are quite fast.47 e for last haste debuff is probably not worth it as you should not be debuffing tanks in rvr as it increases spike dmg.