Hello,
Thank you for your kind feedback, it was pleasure to read these lines :)
As for additional entities you mentioned, to be honest I do not have plans to add them as in this case mod would become too OP, see main thing here is you got only 150 cells each of them you could trade either for item request, energy, crafting template, memory or items import. Main philosophy is you kind of trade vacant cells for features you want chest to perform. But in case of introducing dedicated "chest" for memory cards is simply gives you literally unlimited space. I will think about making some kind of either "Templates MK2" or simply another very-very expensive module that virtually doubles all templates output rate.
Plus I have to use only vanilla assets (as you might notice most of icons and entities are vanilla with changed colors as I do not have any illustration or 3D skills) and for example Storage Card for 128KB obviously must be some kind of vanilla speed module icon but with 4 LEDs on top, but factorio itself does not have one so I'm really limited in assets as I do not want to steal ones from other mods
What will be done 100% in nearest versions: most of buildings crafting templates to serve as basically your mall (chests, assemblers, inserters, belts, power poles)
Also performance is a great-great issue, I used special native factorio prototype called "linked-inventory", it works extremely fast because game handles it itself without me worrying about it. See each second (60 ticks) my script must do several things: look each of 150 cells for filters, take all chest contents and decide whether some items must go into storage, put lack of items from storage + craft things that are requested (which also requires check if there are both enough ingredients and enough space to put result), Adding dedicated requester chests might slow this down dramatically as you have to take all actions above and multiply them for each chest you built in a world + add my lack of LUA experience and you get laggy mod with tons of errors (I'm not completely sure is works properly at current stage though :) ). BUT if you really need that feature there is a mod "Quantum Storage" that introduces exactly what you need: requester chests for background storage, but it cannot craft things and have limited storage of 99999 of each item (https://mods.factorio.com/mod/QuantumResourceDistribution2)