There's a problem with activity that is the result of various other problems. Unfortunately, even with larger families we won't see much of a difference. In fact it might even be worse.
We had much larger families last round and while it may have been good for some people, it left the possibility open of having a large family full of inactives. As one of the few active people in my family last round, that was incredibly frustrating.
Having smaller families has made this less of a problem, although it is still not quite right. I personally think even smaller families would be better, with the opportunity to ally 2 other families again. This would give you the opportunity for social experience you're describing through a 15 person alliance, if we had 5 man fams as Render is describing.
Unfortunately, the smaller a family gets, the more painful it is when any one member goes inactive. It's a complicated problem with pros and cons for going larger and going smaller.
The root problem though isn't family size, it's the impact inactive players have on families of any size. There are a few ideas floating around that are directly or indirectly related to increasing social activity and/or easing the pain caused by inactive team members:
1) "State of Family Affars": http://imperialconflict.com/forum/viewt … ?id=181975
2) Illegal Alliance Rules: http://imperialconflict.com/forum/viewt … ?id=182424
3) Fam Bank: http://imperialconflict.com/forum/viewt … ?id=180385
4) Sending aid on a regular basis: http://imperialconflict.com/forum/viewt … ?id=180882
5) more even gameplay: http://imperialconflict.com/forum/viewt … ?id=181985
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