That’s awesome! Keep in mind you can always start slow. I spent a month or so just building up a bit of a BTC base in case the price dropped significantly and some bills came due.
For 1) the fees associated with strike bill pay are based on the amount of trading you did the previous month. I think the highest fee they charge is <1%. I try to offset this buy buying things with a Gemini cc which will reward you 1-4% in BTC for your purchases.
For 2) It probably depends on the size of your bills but overtime if you continue to spend less than you earn and BTC continues to appreciate your BTC/bill will go down and free up BTC to move to self storage ( or at least that’s my plan). Hope this was helpful