The best replacement for 802.11g is 802.11n.

The best alternatives to 802.11g are rated as following:
★★★★★  802.11n
★★★★  802.11b
★★★  802.11a
★  802.11ac
★  802.11bg
★  802.11n range
  bluetooth
  802.11g
  802.11i
  802.11

Your alternative for 802.11g is not listed? Suggest!
Speaking about 802.11g, one probably shouldn't forget about 802.11b.

Other search terms related to 802.11g and their ratings are:
★★★★★ 802.11b
★ 802.11n
You have in mind a companion for 802.11g and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of 802.11g in all years. Click on graph for more.
802.11g
802.11n
802.11b