Sensible Engine Mods

What would you do, to gain a bit of extra power but without spending silly money? My thoughts were the following:

-Panel Filter
-Matched Inlets
-Decat Exhaust
-Remap

I'd guess that shouldn't cost much over £1k.
 
They're the most obvious things to do. Past that you're really starting to look at cams which is a fair bit of dosh