Interesting story.

its nice good

For Shirou's servants:
- Artoria (Saber/Alter S./Lancer/Alter L.) since Shirou should still have Avalon on him and to see his reactions to Artoria's different configurations
- Any Saber Face same reason as Artoria, just to see Shirou's reactions
- Mordred to see how she'll react to Shirou's relationship with Artoria, and she could try "stealing him" from Artoria
- Musashi not much reason only to see the interactions between her and Shirou
- Siegfried just based on Fate/Apocrypha where he says he wants to be a hero of justice
- EMIYA only to see how Shirou and his future self will interact infront of all of Chaldea
- Ishtar similar reasons to EMIYA since she pretty much looks like/is his lover
- Chloe von Eizbern only to see his reaction to a female loli Archer
- Cu Chulainn just for irony
- Ereshkigal similar to Ishtar
- Kiyohime
- Tamamo no Mae she's best waifu (cue Nero fans glaring and shouting death threats at me)
- Illya depending on which timeline this is
- Irisviel if Illya is summoned
- Kiritsugu kind of like a huge middle finger to both Shirou and EMIYA
- Semiramis only cause Shirou looks like Shirou Akamusa
- Shirou Amakusa only to see the interactions between all the "Shirou faces"
- Jack if you want Shirou to be an older brother for like he is for/ was for Illya
- Jeanne only cause why not?
- BB, Meltlilith, Passionlip for "Sakura faces"

XD just for kicks it would be interesting to see Archer's reaction to having shirou as his master XD

I say lancer arturia scathac and Siegfried for shirous servants

Definitely Arturia

Maybe for Archer Class, EMIYA probably, they can work together well and will have a great connection due to them being the same person. For Saber, well Arturia is definitely my choice if he has Avalon inside him.

Shirou x artotia (saber)

Pleasd arturia

I cannot tell you how long I have been waiting for a story like this. Keep worrying - it’s good!

I think two of them could be scathach and jean d arc would be a good match.

If Avalon is still a part of him, Arturia will definitely be the most compatible...Followed by others...

Good chapter

Saber: Lancelot, Mordred, Musashi, Okita
Lancer: Cu, Scathach
Archer: Atalante, Tomoe gozen
Caster: Medea, Tamamo , Davince
Berserk: Nightingale
Ruler: jeanne, Shirou amakusa

Awesome I love character development. you've seen part 2 of F/GO ? where? wait if the grail was still tainted how did Chaldea get created? hm... well i'm assuming that Arturia is guaranteed so other then that...Karna? i effing love Karna and I think he and Shirou would get along.

For Heroic Spirits, here's my list of recommendations and class selection. If you can't decide between which Servant should take up which class, you could always hold a poll to let readers decide. or ask them to leave in reviews which Servant should be in which class and explanation why they would be fit for the class the reader assigns them to.

Ruler - Jeanne d'Arc, her characterization in FGO and F/A makes her a really great powerful support Servant

Avenger - Jeanne d'Arc Alter, powerful Servant that can dish out so a lot of damage to enemies and her Dragon Witch Skill allows her to control Dragons

Saber - Arthuria Pendragon, his original Servant in the 5th Fuyuki HGW and his main love interest.

Archer - Either Ishtar-Rin or Chloe von Einzbern to be part of reunited Emiya family. Or Tomoe Gozen is combination of one of the best designed waifus in JP so far and powerful Archer Servant whose NP is throwing a target into the air as she shoots them with her bow.

Lancer - Scathach, she's a godslayer and taught many Irish heroes before including Cu Chulainn. So powerful that she became something of a Divine Spirit herself.

Rider - One of the Lancer versions of Artoria Pendragon can go here. I recommend them because of their NP that is equally powerful as Excalibur, Rhongomyniad. Plus Lancer Artoria can serve as a romantic rival to Saber Arthuria over Shirou's love and affections, especially if Lancer Artoria decides to steal Shirou away from Saber Arthuria and make him her bride, wife, and new Queen of Camelot. Their connection to each other is established through Avalon inside Shirou's body, which resonates with Lancer Artoria and in turn influences Shirou, compelling him to accept her as his King, lover, and "husband" and become her bride, wife, and "Queen of Camelot"

Caster - Either Dress of Heaven (Irisviel) as part of Emiya Servant family reunion, or Tamamo-no-Mae the best support Caster waifu in all of Fate. Tamamo-no-Mae is just perfect wife material.

Assassin - Shiki Ryougi, she's the protagonist of KnK and her Mystic Eyes of Death Perception means that she can kill even gods if she sees their "lines".

Berserker - Either MHX Alter or Nightingale. With Nightingale, she can be a support Berserker serving as the team's medic. MHX ALter fills the role of a alternate dystopian futuristic Heroic Spirit

Gunner - EMIYA Kiritsugu as part of Emiya Servant family reunion. Plus Shirou gets to see what his father probably was like before he met him

Saver (Heroic Spirit of Salvation) - Amakusa Shirou Tokisada, he shares the similar goals with Shirou in his wish to save Humanity

Launcher - Prisma Illya as part of Emiya Servant family reunion.

Monster - Arcueid Brunestud, main heroine of Tsukihime. Both her and the series deserve some attention and recognition since all of Type Moon's attention is on the Fate series. She is the White Princess of the True Ancestors, the high tier vampire species in the Nasuverse followed by Dead Apostle Ancestors and Dead Apostles. She actually appeared by as the Servant Monster in the EXTRA-verse, so it does make it possible that she can appear as a Servant.