Aloha,
ds2, who will be 3 in December:
Take off their clothes and/or put them on? No
Put on their own shoes? No
Put on a coat? No, but can take it off.
Pull their trousers down? Staggeringly yes - can pull down, sit on potty and pull up again! This is very recent though - has only been toilet trained for about a month. His older brother wasn't toilet trained until after his 3rd birthday and I spent the summer before he started in reception class desperately trying to get him to pull up his pants as well as his trousers and get them up without the crotch being twisted halfway round the back of his bum
Ride a scooter? No, also can't pedal
Catch a ball? No
Brush their teeth? No - can suck toothpaste off the brush very successfully
Climb into their own car seat? No idea - if let loose into the back of the car, clambers over into driver's seat and tantrums about wanting to drive
Get onto the toilet? No
Make a sandcastle? Well, sort of...
Use a knife and fork? Can use a spoon and fork, but prefers fingers - only uses spoon properly for ice cream or yoghurt
Walk upstairs like we do? No. Climbs up on hands and knees, comes down on bum or hanging on to bannister with both hands
They all develop at their own pace - I am not concerned about ds2's development at all. I'm not going to tell you not to be - he's your son and you know him best, but he really doesn't sound at all unusual to me. And I would lay odds on him becoming far more independent once bubba no.2 arrives (after the inevitable short backslide into babyhood again - even my nearly 5 year old did that when his baby brother arrived).
HTH?