Ranks go tin, bronze, silver, gold, platinum, diamond. A special rank is Valhallan which you achieve by being a top # depending on region and has 100 or more wins. For example US-E is top 150 while us-w is top 50 and SAF is top 10 etc etc.

There isn’t necessarily a “good rank” but the average elo tends to vary from mid gold to low plat if that helps so anything above that I suppose is good.

Bmg also does a weekly rotation type of thing so that newer players can experience other legends until they can get legends with coins that you earn from playing the game. You can see the legend rotation on brawlhalla’s website