Battle Athletess Daiundoukai (TV)

both comedy. 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. 

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).  

If you're into cute girls doing hi-tech sporty things, then you may want to watch these 2 series. The contrast though is that Battle Athletes Victory focuses more on individual sports while Extreme Hearts is more into team sports. Also, "initially inexperienced lead crossing the road to glory" storyline. 

both anime is set in futuristic time, have a school that make them develop their skills, both is aiming to go the galaxy and make their dreams come true...  

similar as far as characters having a "overall" goal and "training" or. both have fun characters though aria IS SLICE OF LIFE. 

both in space, good comedy, a little wacky, and main characters are a little annoying but there's character development. plus there's competitive spirit part in both anime. 

both have like action/sports/excitement thing going on, and anna and chris are similar and awesome. both have similar themes. 

both have main characters that start off a little iffy and there's great development by the end both comedy and bav has shoujo-ai which adds to the comedy (not yuri) 

both are very good comedies and doesn't take sports elements too seriously (most of time anyways)