I've been looking for something kind of like this for process or flow charts, but automatically places the blocks/nodes, yet allows "hints" to nudge things as needed. Example syntax:

  Title:    // chart page title
    Flow-chart Shorthand Rough Draft 

  Decision:
    Too big a project?
    @Yes #label02  // arrow to #label02
    @No #label01

  #label01

  Process:
    Make lemonade
    $options: no-point, foo   // no arrow-head, etc.

  Process: 
    Sell lemonade
    $linetext: This is text near line coming to this process
    $hint: north-east   // positioning hint

  #label02

  Terminator:
     End

Perhaps the hints could have an optional strength parameter: "$hint: north-east 60%". If you invent an implementation, I'll give you lots of Ycombinator points. I once used a tool called "graphviz" to kind of do this.