Restructuring the leagues is critical to getting the better 25-35 year old continuing their cricket and by increasing this pool you will improve the younger players. As the better adults drop out of cricket their talent, experience and energy goes with them which is a loss to the sport. To improve is see two starting points;
1.
To make cricket more successful it needs to become more family friendly. Football and Rugby, at what ever standard, is finished by 6. In the winter you can be a bit late to a family or social event yet still participate in a social life outside of sport in the evening. There will be the odd game that people have to travel for, especially if you go through the leagues, but you accept that if it's the exception rather than the rule at most levels.
Cricket needs to focus on making better more rounded people not club-men who spend every waking hour at the club, you will get those anyway, the ones you lose are the people who have families or outside commitments that cricket can not accommodate due to such a unsociable finishes.
T20 isn't the answer, over rate will only improve it to a minor extent and it must be enforced- which is unfair on the umpires or volunteers. The problem of "too many cancellations" will be mitigated if cricket is a more social sport, for players and their families, to be involved in. Earlier finish times will assist this, not completely but will help it.
2. Cricket needs to have a pathway to the top - the Home Counties Premier League (HCPL) is a ceiling that no one can go any higher in this area. Combining the leagues is the first step to consolidate the leagues to allow cricket to become more of a national game rather than a regional game. Once this is achieve people will start to believe they can be come "the best they can be" and we could see the counties challenged by people with resources rather than the current stagnant system. Seeing an RB Leipzip come through the levels in German football is exciting. To see similar in cricket would, I believe, increase both hope, interest and funds in the sport.
Broader topic I know but cricket is struggling to keep players playing and the above a start to improving it.
@Woodyspin - agree travel isn't an issue if you have an earlier start/finish time -personally I think the finish time will have a greater impact :-)