I appreciate the advise, but I'd rather not blank the EGR valve.
If you want to increase power/ improve MPG how are you going to do that if you wont get a remap or fit an EGR blanking plate?
Here are some suggestions -
Service - a fresh air filter, fuel filter, and oil change/ filter can help - and is good practice (if not done recently) i change my air filter avery 6k/ 6months - not the over-long recommended interval
The EGR contaminates the inlet manifold with carbon, this mixes with the oil from the breather, forming an oily "goo" the inlet manifold needs taken off and cleaned - ideally you want to fit a solid EGR blanking plate to stop this happening, again, and again, a breather catchtank will help prevent the inlet (inc. manifold) being contaminated with oil
Loose weight - if you want more performance AND economy a good way to do this is to reduce the weight in the car - start by taking a bux and filling it with all the un-nessesary junk in the doors/ boot/ glove compartment you don't need that you are hauling around - car will run nicer too when it doues not "rattle" down the road - remove the subwoofer/ fit a lightweight one - ditch the spare wheel - to go further costs money/ effort, but a lot can be done, the rotating mass is important, things like the AC, waterpump, flywheel, wheels/ tyres
The stock exhaust is heavy, fiting a lighter one that is freer- flowing (or specific components like the restrictions in the exhaust like the CAT/ back-box) can help the performance/ economy/ + reduce weight (killing more thane one bird with one stone, as it were)
the lightest possible wheels can reduce, rotating mass, unsprung weight and overall wieght tyres ditto - some tyres are specially made for better economy and can have a significant effect, narrower, smaller tyres are better for economy, keeping the pressure high reduces rolling resistance
Finally, (as mentioned) a remap probably makes the biggest difference of all, so is a cost effective way of increasing performance (a lot) and economy (a bit)
If you do nothing/ change nothing - you will improve.... nothing - a solid EGR blanking plate costs under £5 well worth doing emptying the car costs nothing, pumping up the tyres costs nothing - but for much after that - you need to put in more to get more out