It's hard to say about other counties really but the past few intermediate teams in kildare have been very strong and its a competitive championship. Maynooth, Confey, Ballymore, Kevins all had strong hardworking teams and had to overcome the likes of Jtb, Monasterevin, and a host of dogged, if not some of the most talented, teams.
Longwood were a very good junior team with a few fine footballers and had high hopes for their intermediate championship the next year after winning. While I don't think Ballinabrackey are all that talented, in my opinion the hungriest, hardest working,most professional and well drilled junior team will win the county champ as there is not much to split between the teams otherwise. From there any team has a great chance of winning Leinster.
In the senior I cant claim to know a whole lot about the Dub championship, but it is very competitive with Kilmacud, Vincent's, Brigid's, UCD, and Ballyboden . Sure from sheer weight of numbers there's bound to be a few clubs with lots of very good club footballers in addition to the likes of Kilmacud with blow ins from other counties bolstering their team.
Also the mentality for the Leinster senior champ is different. With the likes of Celbridge, Larries and Athy winning county championships is what they work towards. It means so much to them that they don't think about Leinster until the final whistle in Newbridge or even until after the piss up that ensues. And who could blame them. While the likes of Moorefield, Rhode, Portlaois, Kilmacud etc. have an eye on Leinster from the start because they are used to winning the county championship and see it as a stepping stone to bigger things. They also benefit from the experience of playing in Leinster (something which could be seen in Athy's defeat by Garrycastle at the weekend)