Current NP levels of each in brackets
Melusine (NP4), Crane (NP0), Morgan (NP3), Caren (NP2)
SIbuki (NP0), SSkadi (NP1), Archetype: Earth (NP1), Lady Avalon (NP1)
The first choice is either to boost a damage dealer (and possibly coins towards a L120 Morgan if I bother with another Buster AoE after Melusine and Demon King Nobu) or to finally get Crane, who is just waifu tier since I can't even work on her skills before Christmas lotto.
The second choice boosts damage (Arc / SSkadi) / stalling (Lady A) or gets me SIbuki who wouldn't be useful as a primary damage dealer but can still have multi core support with her skills. NP2 on either support would also let me put another NP2+ on my support list to replace NP1 Oberon.
The second really makes the most difference, especially for Arc, the first would just push the damage dealers up a little higher given they already have multiple NP levels. And getting Melusine would mean picking someone else in Destiny Order. But still, they are all good servants there. The NP boosts in the second aren't required beyond Arc. So a hard choice.
---
Also trying to make a decision on Destiny Order.
Saber - Original choice of Nero Bride is less useful after getting NP1. Push her higher or just get a missing servant? Ibuki, Sigurd, Charlemagne, Beni-Enma, Musashi, Medusa, Shiki, none I particularly care for and not have any I really want to push further.
Archer - Super Orion for using, Summer Artoria for Waifu. Coin flip.
Lancer - Melusine is top choice unless I get her in GSSR. Otherwise I might try to boost Scathach NP.
Rider - No one I really need to roll for her. Maybe I'll just choice Summer Artoria Alter.
Caster - Probably Crane for waifu or Murasaki NP boost.
Assassin - Kama NP boost.
Berserker - MHXA NP boost.
Extra 1 - Summer Artoria for the waifu.
Extra 2 - Probably an NP boost for Draco so she can actually be useful.