you dont need to bring shirou here,because he will overshadowing issei as MC just bring EMIYA if you want
he can besummoned as Archer,Assasin,Caster and berseker.

Let's see friend, all the names are capitalized, you can't put a lower case on a name, and the first letter of the first word of the row is also capitalized, always. Before continuing to write, he learns to correct misspellings that not even a first-year high school boy has.

I'd suggest you download grammarly to have another look at your chapters. The story is great but you really need to fix that grammar.

Holmes, Li Shuwen, Zhuge Liang, ROMA

The quotation marks are all over the place. Though I wouldn't mind having to figure out which ones are dialogue.

NExt

I thinck 5hat it will be better to summon Arthuria

Nice and interesting story

interesting but grammar needs work as you've left out words that would make your sentences flow better

explicación simple

Well I vote for Martha. She is a great servant with a dragon taming ability on top of the saint status. But I think she is suit to the rider class more than ruler class though. Another good thing about her is that in legend, she is the one who work directly with the christian god. So it will be a huge surprise to the heaven and Grigori factions. I can imagine the surprised faces of Michael, Gabriel, and Azazel from afar.

I think issei should summon Xuanzang as one of his caster or ruler servant. I actually thought that issei would summon Tamamo as one of this servant batch because Amaterasu is also present in the summoning room, so she can act like a catalyst for the summoning.

Good chapter so far and I think the first four servants were believe to be archer-lil gil, saber- mordred, lancer(best boy)- cu Chulanin and last has to be archer or avenger- oda nobunaga I think. The fifth servant has to be my boi astolfo since its gonna be funny just for comedy.

Also are you gonna plan issei to summon any hindu heros since it be real the hindu heros are really powerful if so let issei summon arjuna or karna but genderbend as in female version or not which I fine with. But if the whole supernatural world find about the heroic spirits stuff no doubt in my mind they will attack Issei for bring back their heros and etc. If that were happend aleast let issei speak on his part and as well the heros who came back to life to hear their story, one thing I really hope this doesn't happen in this story is that people other than issei can summon heroic spirits cause to me it's going question of how they able to summon them if the old man only tell issei of how to summon them and stuff but again it's your story and plot so I respect your decision for the story and etc.

And hopeful the last thing I wanna talk about is the harem is it going to have servants in the harem along with the canon girls(Rias,Akeno,Asia,Etc) and even add Yasaka due to the chapter 4 between the two and maybe in the start Yasaka sees issei interesting then later formed into a crush from there to love. I really hope the female servants are in the harem since issei is still going to be a harem king and future hero.

P.s I have some form of ideas if you willing to hear

1. Since issei summoned a certain lancer as in Cu Chulanin have his mentor Scathach the queens of shadows appeared in the story in future chapters since she never technically "died" in some shape or form. To train Issei as well in guiding him since after all she is a mentor of many famous warriors and heros alike. Maybe have her appear after the fight with Raiser or during the underworld training camp since she can see potential in Issei who could be her best student due to being the Red Dragon Emperor and even surpass her students or maybe herself after all she is a badass God-slayer who kills gods for a living. Might as well have both of them fall in love by issei helping Scathach to find joy in life instead of wanting death in which cause Scathach to fall in love with him. This is just a possible idea I came up with due to be my best boi lancer being summoned.

2. The Hero Faction will take notice of Issei in some point in the future and try to convince him to join the faction since he has the power of the Red Dragon Emperor and the ability to summon servants a.k.a Heroic spirits of the past,present, and future. With Issei refusing since hero faction wants to destroy the supernatural world or something similar to that I believe since it had to do with supernatural world. The Hero faction hunts down issei in forcing to join the faction with a battle between the hero faction and issei group in which issei takes the victory then capture them and question them. Some point later trying to convince them to join issei group to see the true meaning of what takes to be a hero.

That all the ideas I have so far, I know there more scenarios but I forgot what they were.

P.s.s
Is Issei going to become Rias servant ?
If not then have two of them forge a alliance to support one other of aiding each other in dire situations such as Raiser battle and etc.

ASTOLFO

Saber-Musashi Miyamoto
Archer-Arjuna
Lancer-Karna
Rider-Ishtar
Assassin-Ushiwakamaru
Caster-Nitocris
Berserk-Kiyohime

fem!Karna-pseudo-servant then the original Karna,class of Lancer and Archer.