Tradeoff: how much complexity

Filler - summarize various options. Maybe a 2-d graph with:

    c |
    l |
 ^  i |
    e |
 i  n |
 n  t |  multiple knobs,
 c    |  requires multiple
 r  c |  fallbacks, but a
 e  o |  non-SR solution works
 a  m |
 s  p |
 i  l |
 n  e |
 g  x |                           require more uniformity,
    i |                           interop testing is easier,
    t |                           but writing correct server
    y |                           requires more effort
      +------------------------------------------------------
         > increasing server complexity