thanks for all the answers.
Showah32, the order 3 is very needed because R'lyehs troops requires a lot of gold. Their "chaff" tend to get slaughtered pretty darn quick too, so until you can get some stable summons, you will need to reinforce your army pretty constantly.
The Luck 3 scale could be traded for more dominion or magic paths on the pretender. But I feel that the Aboleths have a higher need of alchemising gems then other nations, so every little extra I can get helps.
I will try out a Wyrm pretender in my next game. I have been going with a w1a1 Kraken. But going to try a W1A1N4 Wyrm, with my eyes on some heavy Naiad warriors summoning once I get Conjuration 5. I believe that with a slight N4 bless they might be more cost effective in an MP game then the Sea trolls. That is ofcourse highly situational
As you pointed out, the conjuration tree gives both Tiamat and Dark knowledge spells. And compared to the Enchantment line lvl 5 conjuration gives a few useful summons within Rylehs reach, where enchantment starts to pay off first at lvl 5 with hidden in snow. Unless one considers the claymen worthy to summon.
Thaum can as noted earlier be avoided because of Mind Lord abilities. Evocation starts to shine first at lvl 5 with Falling frost. Since cold bolt/blast are the only other easy options on the way.
So I'll try Conjuration 5, Construction 4, Evocation 5 in that order. Time to actually play some MP. I will most likely get slaughtered