I have been in many, both group RPs and 1x1's.  I have found that the key is to have an open ending that is easily adaptable in mind and when you feel interest flagging and momentum slowing you move towards that end. It has worked so far, better in some cases than in others.  I also tend to plan small as far as time passing IC. My IC time tends to be measured in days while the OOC time that passes is months.