Firstly I don't know how to multi quote but to Tug- It is not the time frame it is the losing 8 games from the season. 4 home game per team, it doesn't generate enough games in that respect. And before someone mentions an expanded league cup, groups, just look at the crowds in the competition just now, even in derbys. It would never make up the shortfall.
As for not having enough good enough team, I ws refering to an 18 team league and we definitely don't. For a start you would have to get rid of any stadium requirement whatsoever as at the moment you could only make 18 teams that meet the current requirements by going down to the 2nd division and then into the 3rd. At the moment we could just about get away with 18 teams but then we would have Cowdenbeath, Morton, Brechin etc at the top of the 1st battling to get into the top league. There is just not enough quality and enough big clubs to sustain an 18 team league. Also there would be so many meaningless games in an 18 team league that it would be so dull. At the moment only 1-3 qualify for Europe, it would create far to many dead games in the middle of the league.
The only options that will be seriously considered I think are 10, 12 or 14 team league.
Raith Rovers, Dundee, Dunfermline, Falkirk, Partick Thistle all have the grounds and top flight experience. Livingston will likely be promoted this season so thats six teams with everything in place already. So all would likely come from the first div by the time change came about. As for the teams battling to get into the SPL in the future would they not have to show there ambition by meeting the required criterea just like everyone else had to do.