MC roller coastered the North when they were ahead of the curve with cap ships. The problem is that now even the small alliances can field large numbers of these. This means that MC would still work as a merc force but not as a solo operation. They shot themselves in the foot by trying to take space and claiming they were still mercs. If they had remained unbiased, they would still be viable as whoever hires them needs to know that they have no agenda of their own. A good
neutral merc force still has a role I believe. MC appeared to be universally well regarded while it's neutrality in the reasons behind conflicts was maintained.
Tri had a bust up between the carebears and the PvPers. PvPers left and the whole thing imploded. Stuff could probably have been reconciled but one corp blew up another's mothership and that kind of prevented it

. Lots of whinging about moons going on too.
Just realised my sub has lapsed and my skill has finished training. Damn.