Chad, we do read to him a lot. We're worried that it's too much. We're fearful that it was all that reading that has now caused the echolalia where he repeats them.
Nah. I don't think there is a "too much" here. 1-1 time and communication is always positive. Just make sure you're not the only one communicating. Getting info back from him is very important here. Keep him exercising that skill as much as you can, even if you have to stop every page to pull feedback from him. Can't stress enough how much better it is to keep it two way communication rather than daddy reading and kid listening.
Sounds like you're on the right track. It's also good that you have another kid as social skills and peer interaction are going to be a challenge for him. That is one of the ironies of the autistic child - they really need a sibling to practice their social skills but many parents are so afraid of a second autistic child that they never have any more kids.
He's not a big fan of getting his hands dirty, but has really started to enjoy this and playing with Play Doh.
That's common. He doesn't like the sensory input he can't remove.
For his play, we're working on doing things that require taking turns and sharing. We have also tried to spur some imaginary play by getting him to treat his Elmo like we treat our 6 month old daughter ("give Elmo some milk". etc.)
Role playing is good. Some kids respond well to rote repetition of social situations. You may end up having to do it again with the baby as he may not transfer that knowledge from Elmo to the baby. It will help him learn how to interact with the baby faster since it is not new material, though.
So far, he doesn't really have tantrums or meltdowns. He'll cry when he's not happy ("okay, time to put the train tracks away"), but the crying is short-lived.
Reasonable at that age for any kid. One thing I've noticed in dealing with many parents of autistic kids is that if
anything happens they immediately assume it is the autism and don't understand it. They miss the forest for the trees - don't miss the age appropriate actions for what they are - age appropriate. It's not easy to draw that line, and sometimes you'll be wrong, but when a 5 year old kid runs and falls down it's NOT always a motor skills problem. Sometimes he's just a 5 year old that tripped.
In terms of senses, he doesn't appear (to my untrained eye) to be sensitive to lights or sounds and such. He walks up to the Christmas tree and likes looking at the lights and ornaments.
A consistent fascination with lights could be a light sensitivity. It doesn't appear to be causing discomfort, which is the real issue, so that's good. Some autistic kids will seek out and be drawn to light sources, especially colored flashing ones (pinball). Of course, the tree is pretty and big and right in his face, too, so he could just think it's pretty and cool (which it is).
We're just bummed that he doesn't show more emotion like a normal 2 1/2 year old. We took him outside for the first snow of the year over the weekend, and he didn't crack a smile. I know there was a lot for him to digest (what is all this white stuff? Why am I stuffed into a snowsuit like some kind of sausage? Why is it so friggin cold?), so maybe I was expecting too much.
That's a difficult thing. I truly believe that they feel the emotion. I just think they don't feel exactly what you would expect because they view the world differently. They also don't express it. Don't ever stop going to the effort to expose him to positive things like that - you may not get the feedback you are looking for but he is getting the benefit you wanted him to have. Consider this - for the dozens of times that will happen, it will all be worth it the day you hit the right stimuli at the right moment and he opens up and lets you see. I've seen large men break down and cry at that moment. I've done it myself a couple of times when weeks of frustrating skills work leads to a sudden ability to consistently hit a baseball and the kid smiles and won't put the bat down.
EDIT: BTW, sorry for the especially long wordy posts (even for me)... if it's too much, email me and we can talk there.