Who should be on Friend Support

Ok here we go i'll help to the best of my ability also grails don't boost in much in the way of stats so just say them and grail your favorite characters.

Berserker- For berserker its down to either Raikou or Cu (alter) I would go for cu for the simple reason it looks like you grailed him and he has maxed skills so show that love, plus looks at your friends list and look at how many Raikous there are compared to cu alters at least on mine there's a lot more Raikous.

Saber- This is the hardest one for me to decide on, but I think if your looking for friend points go with saber alter and have a k-scope on her for farming plus she's grailed so if they sort by levels which is what I do she will show up with all the 5 stars.

Lancer- Go with Elisabeth for now since she's np2 and has higher level skills, but if you continue grailing cu to at least level 90 put him up there since most people will use simply for the novelty of using grailed cu.

Archer- Emiya no question just saying I almost never pick 3 star and below servants since I have them and there's no reason to double stack them like double waver.

Caster- Tamamo should go in your caster slot since she's both a 5 star and a pretty good one at that and she is also the main support for a whole genre of teams, the art team. Get her 3rd skill to max as soon as possible and also I would recommend maxing Helena's first skill since its really useful for farming and if you slap her on the all slot you'll be rolling in friend points.

Assassin- First level up Emiya and put him on there since he works better as a support then Carmilla since he can help with arts teams and can generate more stars.

Rider- Kintoki since he has higher level skills then Martha and Ushi and he is better in most circumstances.

I would say, it depends on the weeks : farming or events.

For farming weeks, I would put AoE servants like Saber Alter, Raikou, Liz, Emiya, Helena and Martha with a starting NP CE like Kaleid, Imaginary Element, Sumo CE...

For events, it depends on the missions.

Expect raikou to get the most use and cu alter or tamamo second. Since raikou covers all farm needs and tamamo all support needs, the rest of your supports would be used primarily for their ability to boss dps. So the best ST servants in each of those classes. Except for lancer. I don't think anyone uses even max grailed Cus (fsn) from lancer support lists because most people have him, as well as his damage being a little underwhelming. Eli lancer would be better there.

Regardless, your three most used servants will always be Raikou, cu alter and tamamo in that order.

Personally, a lot of the time I pick support based on craft essence a lot more often than the servant since I have a solid roster that doesn't require support. During farming I often hunt for the bond level boost or qp boost. During events I look for item drop ce more often than power up ce.

Lacking any of those, I pick servants I like that can fire off their np quickly.