Slip or Mooring Can?
It's all about convenience vs cost.
My club has a tender service that will buzz me out to the boat and back with minimal effort (my dinghy stays roiled up in the lazerette).
But if I return to the club late then I need to tie up temporarily to the dock or get out the dinghy.
I'm not in a slip, but the convenience factor is obvious. Walk right on and off the boat. But it's an extra chunk of $.
Not sure how much the location attractiveness of your mooring ball matters. I rarely sit on the boat at my mooring - when I get there we head out sailing, or I'm underneath dealing with the to do list. But I know people who will sit at the mooring to eat dinner or have a drink.
You need to figure out your own plans.
Does the club offer any services? Tender? Dinghy storage?
2.5 hrs from home likely means you will be headed to the boat for days at a time rather than a quick sail.