Usually I build decks focused on 1 or 2 skills so I'm not interested in having a bonus to all the 4 skills. Plus you now have to stop drawing / playing / committing.
But rogues have a few events that let you add up 2 skills (for example Slip Away) and now you have a +2 bonus which is quite nice ! And a +4 bonus to the basic action (considering that the average basic skill value is 3). For example Jenny Barnes investigates as a basic action with an intel value of 4 but if she plays Breaking and Entering she does with a value of 8, which means she probably can do without committing a skill.
An other interesting thing is that the Winifred Habbamock pack contains upgraded versions of the "2-skills events" that can return to your hand at the end of the turn (Cheap Shot, Slip Away) and so ensure you to get these great bonuses more than once per copy of the card.
Now, which investigators are the most interesting to play Geas with this in mind ?
Finn Edwards plays these events with a skill value of 9 or 10 (3 + 4 or 4 + 4 and then the + 2 from Geas), and up to 12 if playing Lola Santiago. Plus the evade event (Slip Away) can be played as a free action.
"Skids" O'Toole has a 10 total skill value for the 3 non-willpower skills (compared to Finn's 11) but he has the advantage to be able to play Chuck Fergus and these events have the Trick trait ! Most of the time, Chuck will probably not be used for the +2 bonus but to make the event both fast and 2 resources cheaper which makes them free fast events played with a skill value of 9 (+ other passive bonuses) that can potentially return to your hand.
When checking cards containing "add your" to find events adding to skills I also found Ethereal Form, Read the Signs and Spectral Razor so we can look at the 2 rogue/mystic investigators: Sefina Rousseau and Dexter Drake. The first has already the possibility to play an event several times but she can achieve a really high value only with Read the Signs. The second one is likely built around assets.
Wendy Adams has access to this card and can also probably be played without committing cards thanks to her ability to re-draw chaos tokens (and so to try to achieve a less high skill value in the first time). She can play Cheap Shot and Slip Away with respectively a skill value of 7 and 9 and could also use Suggestion with a skill value of 10 in a deck trying to limit the amount of fights. She can also play On Your Own to decrease the cost of survivor events to keep the resources for the rogue ones.
Of course other rogues and Lola Hayes can also play it but I'm not trying to be exhaustive, only to describe which decks I'm the most interested in trying this card in.
And I have not discussed the 2 other possibilities (not drawing and not playing): not drawing seems limiting in case you end in a situation in which you need a card still in your draw pile, and not playing would require committing a lot (with I usually do in Minh Thi Phan's decks) and/or relying on your assets (so no munition, supply, key, ...).