There isn't perfect team comp, mostly depends on situation. For ZL I would 100% exclude SM for example. And more than that, it'll depend on how geared you want your perfect team to be. If you talk of a team that can do all boss and grind together without me insanely hard...
I would say
WM/SW (depending on situations, but not both together, in general I THINK WM better since rework)
lancer/knight (lancer better in most of situations)
any int or agi char basically. (2nd SM sins BM th witch ele alch etc... depending on what you want)
I could tell good point and bad point on most of char, but tbh I would rather try to fix a team composition than give a new one. Ele for example is nice sup and nice damage, though can be annoying for the team because of all these summons.
Basically with this team you have everything needed from low boss to endgame boss. Stuns, way to interrupt, burst, dot, supporting, break... There shouldn't be any boss where you would struggle because of bad team composition.
though SM and AM are only really worth if you can handle them, AM is considered as really powerfull in korea server of what I've heard, but none here is shining in any way. (H could, but he isn't playing, he betrayed us all </3) So you can always take something else instead as long as it has high dps like it.
From strs Zerk is pretty insane now, especially considering half of new items are literally made for her and make her monster dps so you can choose Zerk without regrets.
That's why I wouldn't take her, only because she gets insane with full stuff, but until then I doubt zerk will bring that much to the team. I doubt they want a team comp that will only shine while full stuff.
All this message is about S4 version, since oyu were talking about samael, I prefered to do a team comp about S4 rather than S3 0.18