Why are we not producing talent like we did in the 90s? Easy. Too many imports. It's like the Premiership, you can either have the elite competition where everyone wants to play, and for that the International game suffers (look at England). You cannot have both. But saying that, SL are not attracting the big 'names' from down under to play, like when the seasons were split down under and in England. Gone are the days when you saw proper 'Testmen' like Gary Jack, Bob Lindner, Andrew Ettingshausen, Wally Lewis, Brett Kenny, Peter Sterling etc wanting to play in England. I have said for years, that the English game is either a retirement home for average or 'past it' overseas players, and that throttles the development for the youngsters in our game.
Having coached for many years at both amateur and rep rugby, the talent is there to be seen and have proved it within their pro clubs, yet are shown the door at pro clubs in favor for a 33 year old Aussie who was very average in the NRL.

I think the format of the regular SL season is intimately tied up with the formatting of the international game.

SL needs to have a sensible, and fair, number of rounds (for instance, Warrington, Huddersfield & Catalans get an additional 2pt gimme by having their magic weekends against Widnes, Salford & London, as against Leeds, Wigan & Saints, who play Bradford and each other).

Plus, the Challenge Cup needs to involve all teams and be a straight knockout competition. With all of Super League, Championship, Championship 1 & Elite One Championship you have 44 teams. That would leave 20 spots to open qualification from all teams at all levels who wished to enter, with a subsequent pure knockout over 6 rounds to the final at Wembley.

6 CC Weekends, 26 SL weekends leads to a 32 week (call it 8 month) season, starting the last weekend in February and finishing in October. 5 Nations to be played in June/July, and Autumn internationals to be played in November.

Any stats on number of imports? I seem to remember most clubs having 5+ imports in the 90's

I think it was no more than three in the 1990s.

Why would Sean O'Loughlin play for Ireland when he can play for England?

A minor point, but i would like to point out that Eamon O'carrol plays for Widnes.