Actually, I think Ed was quite lucky to score the MODERN FAMILY gig (I read somewhere that Craig T Nelson was first choice and turned it down). After the re-boot of DRAGNET bombed (a show I happened to like, by the way), it seemed like Ed's career was kind of stalled (some TV guest-starring roles, other TV series that bombed, etc).
The reason we're not seeing more of him right now is, I suspect, because Modern Family is keeping him busy, so either he (or his agent) did a good job at securing him another long-running popular sitcom.