Leeds - Ryanair get you in after 9am, flight back is before 6pm. Airport is nearly half an hour from the city. EI are ~0730 and 1840
This changes come winter.
Business traveller going from Dublin to Leeds:
Ryanair arrival at 9am, departure at 7:25pm
Aer Lingus arrival at 8:05am, departure at 5:40pm
(No clear winner)
Business traveller going from Leeds to Dublin:
Ryanair arrival at 7:35am, departure at 8:55pm
Aer Lingus arrival at 9:40am, departure at 4pm
(No clear winner)
The smart business traveller will be open to doing each leg with a different airline, and that for all routes. I don't know if that happens a lot though...