Well you can talk IPM and PHC, NPK, TTF, BG, CG, AACT and ..... all the other stuff till you are blue in the face and the customer does not care. Being the lost cost provider is DONE - thats called True Green or Scotts. This thread is going nowhere as the real solutions here are not being discussed in depth - real life solutions (not theories) have been proposed here with little to no discussion.
Compelling copy has been stated - I myself have shown you what I do, Compost top dress over seed pretty simple and it works, Bill had some good 'compelling copy' suggestions and so did ecoguy. The rest of this thread is pointless.
The original question was -
What are some practical steps that are easily understood by clients, that maintain beautiful lawns?
Compost and seed - pretty easy to understand.