I think you will find Ecuador to be less 'chaos'. Super-easy approaches and huts at the more popular mountains make it very easy to hit multiple peaks in a short period of time. Never did make it out to El Altar so I can't give you specifics there. I did not use a guide, but there are a bunch of guide services in Quito. I don't think there is much once you leave there. You can also arrange transport through some of the tour operators/ guide services if you are short on time and don't want to deal with public transport. Public transport, however, is quite good in Ecuador. Comfortable buses and we never had a problem hiring rides to get us to where the buses didn't go. I thought Cotopaxi was a more aesthetic climb than Chimborazo but it was definitely more crowded too. I would highly recommend one of the more technical climbs on Illiniza Sur. It is lower elevation but the climbing is spectacular.