The best replacement for asio is wdm.

The best alternatives to asio are rated as following:
★★★★★  wdm
★★★★  mme
★★★  wasapi
★★★  directsound
★★  wavert
★★  asio4all
★★  asis
★★  kernel streaming
★★  directx
★  wdm sonar
★  core audio
★  libuv
★  wdm drivers
★  mme/directx
  libevent
  wdm/ks
  wasapi foobar
  ks
  waveout
  afp
  coreaudio
  zeromq

Your alternative for asio is not listed? Suggest!
Speaking about asio, one probably shouldn't forget about foobar.

Other search terms related to asio and their ratings are:
★★★★★ foobar
★★★★ audacity
You have in mind a companion for asio and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of asio in all years. Click on graph for more.
asio
wdm
mme