What should i do to my 1998 Audi A6 Quattro?

i have a 1998 Audi A6 with Quattro and i was wondering what i should do to it to add some power under the bonnet...... i just want power don't want any of that wining sounds out of the tail end.What should i do to my 1998 Audi A6 Quattro?theres a lot you can do

but if you want to do minor stuff then you can add an air intake to it, headers, intake manifold, exhaust

for more major things you can add a supercharger or turbo, high compression pistons, camshafts and crankshaft, etc etcWhat should i do to my 1998 Audi A6 Quattro?2.8 L V6 OR 2.7 V6 TWIN TURBO ?