Our church has 250+ families, and no deacon. Usually only 1-2 altar boys each Sunday, as well. We do have one elderly gentleman (90+) who has been in the altar for many years helping the priest, so he does a lot of the smaller things a deacon would do. When Holy Week rolls around, though, and the priest has to go through 15 or so services that week with almost no help, you can see him starting to drag by midnight Saturday. Aside from my chanting and a few other readers, there's not much else.