I don't think you are doing anything wrong. But I think that precisely because I think that animals suffering is a bad thing and should be avoided if possible. It sounds to me like you are avoiding it as much as possible--and I assume that when you slaughter them you will do so in a way that minimizes pain and suffering (and likely will not be any worse, and may be much better, than their natural death would be).
So, I may be misunderstanding what you mean when you say that you think suffering is bad but you do NOT think "that [suffering] is a reason for people not to eat animals." My own view is that there are many reasons to try to phase out factory farming, the main two being animal suffering and environmental harm. But both of those problems might be minimized by raising animals in other ways--for instance, the way you are raising your chickens. Others may want to provide arguments for why it is wrong to eat animals no matter what. But I have not been convinced by those arguments, mainly because I don't think that most non-human animals (and all the ones we eat, though pigs might push the boundary) lack the mental capacities needed to deserve moral respect other than the capacity for suffering which is sufficient to provide a reason for us not to make them suffer (all else being equal).