Former marketing man @ Streum On Studio. Jazz enthusiast. Memelord.
Currently at Focus Home Interactive.
Mainly for balancing purposes. The solo Librarian is the only playable class (because scenario) so we gave it multiple spell options to add variety. Transposing that to the multiplayer would make the Librarian overpowered and way more versatile than the other classes with 3 fixed spells, thus impeding the necessity of squad synergy and balance between classes.
We're still taking your feedback into consideration, of course, but I figured it would be useful to explain the intent behind this division.
The AI-controlled terminators do not heal themselves. As a squad leader, you have to keep an eye on their health and order the Apothecary to heal whoever needs it (right side of the wheel). The medikits have a cooldown time and a limited supply, depending on the difficulty. Going through a psygate refills your Apo's medikit supplies.
Of course, in multiplayer or if you play as an Apo in solo Special Missions, Heal is a Skill and thus can be used as many times as needed.