"I think to assign mercury the entire responsibility for autism is letting a lot of other agents and practices off the hook! Check out the work of Mary Megson, a pediatrician who works with ASD kids using Vitamin A therapy, and who suggests some non-mercury-related evidence that MMR induces autism"
I don't see anything in her website showing that the MMR vaccine "induces autism". She may be a pediatrician, but her claims about vitamin A and thimerosal have no scientific backing. A PubMed literature search shows no evidence of any published research by Dr. Megson.
A number of antivaxers, faced with the increasing weight of evidence that thimerosal was not responsible for autism, have leaped to conclude that "well, it's GOTTA be something else in vaccines". This is just as illogical as blaming thimerosal was in the first place. If an environmental factor has to be key, why not blame nuclear testing, pesticides or cellphones?
"One of the main reasons I chose not to adhere to the CDC vaccination schedule for my children was the research around the function of childhood diseases to "prime" the immune system to fight adult diseases. Chicken pox, measles, and other early-childhood diseases get the system ready, so to speak, to deal with other disorders down the road."
Kids' immune systems are constantly being challenged by all sorts of infectious agents, some of which cause "everyday" infections, others of which can cause death or serious injury (most of which can be prevented by vaccination). Getting measles, mumps and other diseases doesn't "prime" the immune system anymore than being vaccinated for those diseases. The contention that it is necessary for kids to get sick with vaccine-preventable diseases in order to avoid adult disorders makes no sense and is not supported by medical knowledge.
"Vaccinated populations have higher incidences of auto-immune illness and cancer"
There's zero evidence to support this claim. If your theory is that getting a full-blown childhood disease like measles is necessary to "prime the immune system", wouldn't all this immune system hyperactivity predispose to getting autoimmune disease later to a greater degree than vaccination? If you get sick with measles you're exposed to a far higher virus load than you would with vaccination, and the immune system would be revved up more.
The truth is that vaccines are a drop in the bucket when it comes to children's immune system exposure to infectious diseases of all types. Their immune systems get plenty of workout even without vaccination. All vaccination does is make it far less likely that they'll contract a small number of diseases that at best make them quite sick for days to weeks, and at worst cause lasting physical damage or death.