A main moderator should never feel pressure to make someone who demands it, the new co-mod. The idea is for the main mod to add his own co-mods, people who work well with him. It is their choice who they make a co-mod.
It sounds to me like people are being a tad pushy and almost sounding demanding that they or their buddies be made a new Co mod. You cannot force a Main mod to make you a co mod.