For next year to avoid the crabgrass issues I would go over the lawn very carefully and mark any even slightly thin areas and overseed to fill them in. Do it like a grid after you mow or something to make sure you dont miss any spots. It might take some time but it isd better than having spots where crabgrass can come in next year.
Most of it looks pretty thick but I can see some areas that are thin from the pics. More than likely those will fill in through normal fertilization but why take that chance, just throw some seed in those spots to be SURE they fill in properly. Its an ideal time to do it right now.
If there are any thin areas like that next season that crabgrass will invade in a heartbeat, the best way to avoid that is to have the grass so thick it has no room to come in and ruin the work you have done.
Keep us posted.