A standard D2 auto is going to feel pretty weak after a D4 that has almost double the power and torque of the Td5 ,as said above check it's all working as it should be then perhaps upgrade as necessary, good news that your oil change has helped though.
The lights that should be showing are abs,tc and hdc together(they shouldn't be showing but if one is then normally tother two are as well)if air suspension light is on its probably because no one has told the ECU that it's been changed to coils.
I'd be more worried about the state of the rear end of the chassis than the oily bits TBH,most of them are reasonably easily overcome but a knackered chassis is a big expense to fix
Possibly low fluid level or partially blocked filter in autobox,if you don't know when the fluid was last changed then do it and replace the filter as well.
Just checked mine from a full tank,this last week using it locally its done 18.7mpg,as said manual box and climate on !!, 9 mile run each way to work and a little round town but not much.