OK... I have updated the home page just a tiny bit.
When you are in each forum, you will see a little dark blue heart to the RIGHT of the forum title.
If you click on this heart, it will store this forum as your favorite forum in local browser storage.
Then, when you go to the homepage, if you click on the new button "Ask a Question or Create a New Discussion" button, the forum you selected as your "favorite forum" will be the forum your new discussion is created.
If you do not select any forum as your "favorite", it will default to the "Beginner's Q&A Forum".
It's simple, but at least you can easily customize the"quick create a new discussion" buttons on the home page to be in your favorite forum.
I've tested it and it works well.
Let me know in this thread if you have any problems.
Cheers.