Main heroines of these two anime, Akari and Noriko are similar. At the beginning of the story they both are weak but talented girls who want to improve their sport skills. Both are bullied by their classmates but they overdo it and go ahead.
Both of them go to space where they have to deal with the aliens.
Futuristic, unusual competitive sport and main character growing into the role is what these two anime have in common.
In Metal Fighter Miku it's Neo Pro-Wrestling - a version of pro-wrestling where fighters (all female) use metal suits.
In Battle Athletess Daiundoukai it's a mix of futuristic versions of some well known sports (e.g. zero-G lacrosse).
BAV anime doesn't do the same joke over and over again and it is quite funny at times and make you laugh. It has lots of characters to but all the characters are likable/memorable.
It has good drama/comedy I guess a little shoujo-ai but the shoujo-ai in BAV is more convincing/funny than the romance in Love Hina. Also it has a plot and that is developed and resolved.
Also you'll recognize Shinobu and Kaolla Su in BAV who were more likable imho in bav.