Hi all, new member, I've been reading a fair few threads here over the past couple of days to get some answers and this seems like a great, knowledgeable, community to get some of those answers

I'm looking to buy my first mechanical keyboard and a couple from KBTalking, have caught my eye.
The KBT Race/Pure are the ideal keyboards for me, the small form factor is appealing (both because of the aesthetics and I intend on carry it around from place to place). However there are a few concerns I have before purchasing either one of them.
KBT Race and Pure:
Since I live in the UK (there doesn't seem to be an existing UK version) and the layout over here is slightly different than in the US there are a couple of key caps I would like to swap out, namely; the top row number keys 2/@, 3/# for 2/" and 3/£ respectively (I wont go through them all). I would like to keep the keyboard looking like I haven't bought after market parts, is there anywhere I can order such key caps and what sizes would I need?
In the case of the Pure, I would also like to swap out the enter/return key cap for the more basic lettering as opposed to the branding.
KBT Pure:
I'm quite drawn to the idea of a minimalist, unbranded keyboard, but these are quite hard to find especially with a UK layout (the KBTalking ones are amongst the few that come close). Unfortunately the KBT Pure, glorious as it is, has a few quirks that I need resolved before I purchase it over the KBT Race.
As a programmer the arrow keys are used a whole lot, and I am kind of worried that using them will be made difficult seeing as the Fn key is directly underneath my right palm!? If I was able to swap the left Windows key for another Function key would I be able to also find a key cap of the right size to replace the Windows key with?
Typing out this post kind of makes my wishes seem like insignificant details now.. I must be missing something..
Could I get your thoughts on either of these keyboards taking in to consideration that they will be used for programming and general typing tasks?
I'd also like to apologize for the poorly structured post and the fact that I'm completely new to all of this mechanical keyboard stuff

Thanks!