My opinion on the new cards is that Simlas is generally underestimated.
Simlas with Pact (or Tempering with Nature's Gift) is a good mixture between Portal and Novigradian Justice (especially with Tempering splitting the points on 3 different bodies), playing for 14+ for 12 (while thinning 2 4p cards and triggering Special synergies twice).
However Simlas is a generally good card, which becomes better in a sensible archetype.
The issue is that Simlas is not (without a Pavetta for Specials) the card that turns the archetype great, but a card that makes a good archetype better.
Elven Seer is also decent, being able to use Tempering on it to play for 9 for 5, while triggering Special synergies and Symbiosis (say from Nature's Gift).
The other 2 cards on the other hand make no sense, the Spell tag is completely worthless to ST (and outside of Gerhard nothing would change if they were blank in terms of tags, which is already a very bad sign) and the triggering number of 3 Specials is extremely high for average payoff.
I get why they assumed the number should be high, given that Specials is a very broad description, nevertheless 3 is far too high.
Beyond that to make matters worse those 2 new Specials do not even fit in the archetype they are intended to be a part of, they do not synergize with Nature cards and are not good enough to be an alternative (and to be honest Orb of Insight and Saov Ainmhi'dh being Nature cards would not be any less realistic than Tempering being a Nature card).
As if that were not bad enough those cards are also overcosted, Saov Ainmhi'dh is basically a Pact/Swallow Potion (without usable tag) for 5 more provision, with an ability that is hardly worth 5 additional provisions, while desiring to be played early, while requiring a unit for targeting and delaying to put out engines/answer engines, which is crucial during the early turns (for all intends and purposes it is a far, far worse version of Crow Mother).
Orb of Insight is also too expensive at being a conditional 8 for 6, which is not meeting any standards applied to 6p cards.
I would say that Saov Ainmhi'dh should either come out after 2 Specials and deal 6 damage, instead of boosting by 6 (which also solves the issue of find any opportunity of playing it early) or it should come out after 1-2 Specials and be priced at 7p, while Orb of Insight should either be a 5 card or a 7p Gold without doomed.