Currently there is no way to change it. But I can dive into the docs again and see what is possible. I just do not want that you have to manually select the install directory on every update.
I am organizing my to-do list with GitHub. If you want to you can check out the milestone for 1.0: https://github.com/Elytherion/tdeheroes/milestone/1
It's not that far away, I'd say!
That's actually an interesting point. It's kind of difficult for me. I mean, the data itself (AP cost, prerequisites etc.) is already implemented as it is shared between the languages. But the translations are a problem because I do not want to buy pdfs just to copy the texts into tables. And because of the wiki is now enabled for the English version, too, all the rules texts must be copied, too - otherwise, the wiki would look weird or a wiki box (this is how I call the side bar with the actual texts from the wiki) might even crash because needed texts are missing (this would not be critical, but it's not a great user experience as well ^^). I spent the last couple of days (probably about 40 hours or even more; didnt pay attention to the time) copying the texts from the TDE Game Reference and inserting styles and line breaks afterwards.
Sadly, I have got a real life ^^ - and a German community for this tool as well. And there is German stuff waiting to be implemented (both data and texts), too.
You might see, there are a few things I have to think of. I would really like to provide English translations for TWK and ACO but time is limited. :/ My current plan for right after 1.0 is to implement the second Aventuria Magic book (German) and to implement the groups feature, which I would also like to have as a GM. Maybe I can manage to copy the English texts in parallel but I am still unsure about if I should buy the PDFs. I do like TDE a lot and I do like the English version of TDE but I do not play TDE in English currently. If I was playing the English version I would buy the physical books and not the PDFs. I bought the Core Rules PDF (for the English version) but besides copying the texts that were missing online I never used it.
If there is someone out there who would like to contribute - even if it is a tiny part - and who got the respective PDFs it would be great. Really. If there are some who want to contribute but do not want to copy and paste text - which I can understand - you can also help me catching bugs or providing early feedback on preview versions. There's only one restriction: I do only provide preview versions for Windows. Well, and you would need Discord.
Somehow I drifted away from answering your question ... but I dont want to delete what I just wrote ...
Anyway, I hope this answer is acceptable!
5.: Well, the light theme is intended to be that bright, it's basically the opposite of the dark theme to provide a hight contrast ratio and to create a clearer UI hierarchy. I once used the app in a very bright environment and I was quite happy it had that large contrast. I would rather introduce a third theme (aka "Not that light"). Joking aside, I will add that to my to-do list.
But cant tell you an ETA.