I think the compost I'm using is 1-1-1, just cheap shit (literally) from agway. The package says 'composted cow manure with humus' and it is $2.50 for 40 pounds.
You know, part fo the problems with overferting come from salt buildup and the chemicals in the fertilizer interacting. There is a chemical in compost that helps prevent unwanted chemical interactions. PLUS if you are running enough perlite, you can flush very easily, so and buildups you have will be easier to clear.
Also if you see signs of burn, back off on your fertilizer- same proportions, but add more water so the dilution ends up weaker.