The best replacement for fire red is leaf green.

The best alternatives to fire red are rated as following:
★★★★★  leaf green
★★★  seeker
★★★  emerald
★  soul silver
★  fire red omega
★  victory red
  heartgold
  green leaf
  pokemon leaf green
  leafgreen
  pokemon red

Your alternative for fire red is not listed? Suggest!
Speaking about fire red, one probably shouldn't forget about cheats.

Other search terms related to fire red and their ratings are:
★★★★★ cheats
★★★ mew on it
★★ gameshark
You have in mind a companion for fire red and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of fire red in all years. Click on graph for more.
fire red
leaf green
seeker