I've got a 3 year old ECS and a 6 month old from the same breeder. The 3 year old is 34 pounds and in my opinion large for the breed (plus for me). His dad was good size when we met the litter and confirmed my choice...as i mentioned him being on the large end of the breed size. The 6 month old is going to be the same. Both great noses and hunting sense...even have the 6 month out already putting/scenting up pheasants.
I've got work to do on the large bird retrieves, he sometimes can't figure out how to grab a flapping bird yet but we'll get there...we've kept pushing in order to get the running birds ahead. Busting Cover, no problem with them except i've noticed when in extremely thick tall catails he's had some trouble but actually gets around pretty good because his small size allows him to weave a bit better...and shelterbelts the same...under low logs/branches he can get through or jump where larger dogs can only jump or go around. Grouse hunting in North MN also has been great with him, he can cut through brush much thicker than some larger breeds. So i'd imagine dove hunting would be no prob, I've wanted to try it still!
We initially went smaller to appease my wife, and I still got a hunting dog. But i've been extremely impressed with their kid friendliness and huntability. The 3 year old loves to swim and is very good at it including water retrieves, don't duck hunt so not sure how that would go yet but prob fine with love of water and retreive...he shakes in excitement when he even sees it...but I can keep him away from it while hunting because he trains/aims to please so well.
Just this weekend he/we put down 5 pheasants. One of them he (3 year old) was visibly birdy coming to the end of a little wooded patch mid corn field. Pheasant didn't flush as we approached, he narrowed the scent to a patch at the narrow end where lone and behold I see a rooster tail and then flushed right then. So neat to see the dog work IMO. I don't talk much about the 6 month old because i'm still working on gun training and obedience. He seems to be very strong though from initial bird encounters...good prey drive. Just haven't wanted to give him 3 guys blasting yet before a few more lessons with with one shooter. Also, the three year old is addicted to fetch...we go camping and he won't leave our side if we have his ball/frisbee close by.
Sorry so wordy, but my experience has been great. I'd love bigger dogs too but compromises had to be made (size - heck she was trying to get a toy poodle for petes sake) and hunting didn't have to be one of the compromises.