Do try to avoid sending unnecessary emails. The CLOG email is essentially for admin, hotline, leaders promoting upcoming CLOG events, Clogprints and AGM/EGMs but not for discussions and chat - there are other media for that.
If you are using a Jotform for pre-booking on walks and cycling rides, you can set the form to close automatically when the event is full with a suitable message to that effect (Settings, Form Status, Disable on submission limit) which obviates the end for a separate email informing members that is full.
If you wish to keep the CLOG stuff separate from your other email, considering using a separate email or else set up an email filter to automatically put CLOG email into a separate folder/label rather than your main inbox..
It is currently not feasible to get CLOG emails as a single daily digest email as this feature is not part of our membership system. There are third party tools but at present these don't have all the necessary functionality but this may change soon.