Yes, I have tried that, my last game I had that Nomad Well and the Mission Church. At a poulation of 400 or so the well would attract up to 60-70 or more nomads which would completely cripple me on food and resources but the Mission Church at the same time would attract only 12- 20 nomads which I could more reasonably accomadate. I found the Mission Church very useful but the Nomad Well- I would always see them filing into town and thought no- not enough food or houses for these mob.
I always start Adam & Eve and build a school to educate the first born children. It takes micromanaging like crazy to keep enough food/wood/clothes/tools, but it's nice to have the buildings up and running and as the kids get old enough to work they have their workplaces all ready to go for them.
I never take on nomads, but what would encourage me to do so is the notion that the population, once exposed to a new nomad brought in disease and it's defeated the whole population has a resistance to that particular disease, to make it less likely to spread the way it did the first time.
This is how I always play [img]<fileStore.core_Emoticons>/emoticons/smile.png[/img]/emoticons/smile@2x.png 2x" title=":)" width="20" />
Trading Posts also can spawn diseases too - apparently brought in by the merchants. I haven't had a serious epidemic in a long time even though I take in Nomads. Maybe it's because I keep my population healthy?