Taylor is going to need some serious gainz to be able to fight some weaker servants at some point or at least contribute, instead of being pretty much helpless and clawless 99.9% of the time, which is going to feel increasingly glaring as the Singularities get harder and she's reduced to a spectator at best, a burden at worst. I mean, she has mentioned that she's not good at staying within her 'supposed lane', though that hasn't happened yet. Yes, she's good for taccom right now, but her present mastermind/tactician role is very replaceable by servants that are much better and more experienced than she is at it, so her present niche can easily be phased out. I mean, this fic is focused on Taylor, power development to keep her relevant in a world of powerlevels is important, lest it just retread FGO, or make her offer little value as a protagonist by not having the ability to change things on her own. There's a reason why canon Ritsuka/Gudako are mostly hollow self-inserts, but Shirou isn't.
Summoning Chiron or someone with their teaching skills actually intact would be useful for rapid development. Hell. Just learn from him in the Singularity. I'm not asking for a super OP Taylor like in An Essence or Silver and Steel, but a happy medium would be nice, instead of Taylor being more useless than a Nero with a fragment of a Saint Graph and a sword, and always watching other people fight and essentially being a damsel in Servant combat, since she, for the most part, can neither contribute, nor defend herself entirely. Sure, she can use some cleverness sometimes so others can help deal with them, like with Altera, or briefly surprising someone with useless insects, but it's either something literally anyone could do, or distracting them and letting the real heroes deal with them. It's chafing.
She seems to be slowly escalating between singularities anyway, getting her powers back at the end of France along with Last Resort, and now it seems like she's getting an upgraded suit and insects back (age of gods insects?) in Okeanos. Meeting Matou Zolgen in London would be a godsend too. Here's hoping that trend continues so that by the time she's in the Temple she can actually hold her own against mid-tier Servants.