Wheelbuilding / Wheel Building / Wheel build help

Hi all, I currently have some Mavic Aksiums with very worn rims on my road bike. As such, I’m weighing up my options for a suitable replacement pair of wheels - budget is probably around £200. Criteria other than that is basically “slightly nicer than the ‘entry level’ Aksiums”.

Questions are:

• Are the Mavic hubs worth getting relaced to some new rims (I.e. are the standard Mavic hubs actually any good? I haven’t had any issues, but I’m after longevity and low hassle.)
  
• If the answer to the above is no, what would be the recommended hubs?
  
• Would the most appropriate (cost, durability and performance) rims be Kinlin XR31s? Any other suggestions welcome.
  
• For the spokes, would regular double butted Sapim be sufficient?
  
  

Thanks