@Carrie585 Hi Carrie, great question and looks like you are off to a great start. Every host has a different set up and bookings need. Some want to push lots of bookings so have IB. You have chosen By Request.
My rule of thumb is if its a high demand season and I know I could be getting multiple offers while my calendar is blocked, I communicate straight away once and if they fail to respond within the hour (which I tell them) then I decline stating not comfortable (like @Kitty-and-Creek0 I am never comfortable when guests dont communicate). If its a slower season I will still respond quickly but I might try up to three times to communicate before allowing it to lapse after 24 hours.
My priority is to maintain my response rate and I worry less about declines as most of my guests seem to withdraw their requests. I will never be top ranked (unless its a very focused search) as there are other IB/new/cheaper listings that proliferate.
You have a flexible cancellation policy so beware guests (including other hosts and friends of hosts) that may use Request to Book to block your calendar for 24 hours at a time. Not responding to a repeated request to withdraw is a red flag and you would be within your rights to report them unless they have not communicated at all, in which case maybe they may have simply not switched on their notifications so yes, always contact CS as well.
But I run a business model that uses both STR and LTR so I prefer quality STR bookings over quantity. You are off to a great start as demonstrated with your reviews.