That is mostly older stuff which is a real different style. I will stick to stuff you can watch free on Crunchyroll(I can get you a free 2 day pass too for watching in higher resolution no commercials) You mention Gundum so a couple recent ones that spring to mind:
Crunchyroll - Gargantia on the Verdurous Planet Full episodes streaming online for free <~simply outstanding mecha show great art/character designs and an interesting story. Another anime fan on the board and I both loved it
Crunchyroll - Majestic Prince Full episodes streaming online for free <~art is kinda different but the story is great
Crunchyroll - Valvrave the Liberator Full episodes streaming online for free <~hit or miss, but when it is at it's best, it is very good
Other stuff to consider, comedy mostly, some of my fave stuff, starting with things currently running this season:
Crunchyroll - WATAMOTE ~No Matter How I Look at It, It <~girl with sever social anxiety issues to the point where saying "thank you" to a store clerk is a major success, she tries everything to become popular, and fails in hilariously embarrassing ways.
Crunchyroll - Silver Spoon Full episodes streaming online for free <~based on manga by writer of Fullmetal Alchemist. It is a fish out of water story, boy from city going to an agricultural college. Very cliche, but the quality of writing makes it stand out.
Crunchyroll - Oreimo Full episodes streaming online for free <~one of the more popular titles lately, very funny but you may have issues with all the otaku references
Crunchyroll - Kotoura-San Full episodes streaming online for free <~bizarrely hilarious comedy about a girl whose life has been ruined by her ability to read minds who learns to make friends. Much much better than any description can make it sound.
Crunchyroll - Vividred Operation Full episodes streaming online for free <~girls fight evil aliens with the power of friendship and cuteness...and boobs and cameltoes.
Some older stuff that is among the best on CR:
Crunchyroll - The Melancholy of Haruhi Suzumiya Full episodes streaming online for free <~my all time favorite anime. It is a slice of life, sci fi, action, romance, harem, mystery, supernatural comedy.
one of my favs as well, even though I haven't gotten around to watching the movie/
Crunchyroll - Mysterious Girlfriend X Full episodes streaming online for free <~boy meets girl, boy licks girls drool, falls in love. Very odd, but oddly compelling.
Crunchyroll - Dusk Maiden of Amnesia Full episodes streaming online for free <~one of the best looking anime I have ever watched.
Crunchyroll - GIRLS und PANZER Full episodes streaming online for free <~WATCH THIS SHOW! It is cute girls, and tanks, and great references, and alot of fun. If it ever took itself the least bit seriously it would have failed, but thankfully it did not.
Crunchyroll - Listen to Me, Girls, I <~18 year old college student ends up raising 3 girls, aged 3 to 15. Hilarity ensues.
Crunchyroll - Puella Magi Madoka Magica Full episodes streaming online for free <~probably the highest quality anime of the last 3 years. Deconstructs(think what Neon Genesis or Watchmen did to their genres) magical girl shows.
Crunchyroll - Toradora Full episodes streaming online for free <~easily one of my top 3 favorite anime ever. It is a romance comedy, but is incredibly well done with fantastic voice acting and some of the best writing in anime.
Crunchyroll - Wagnaria!! Full episodes streaming online for free <~the other one of my top 3 favorite anime. A bunch of people work at a restaurant. They are every one of them neurotic in some way. First episode starts a little slow as it introduces the characters, but by the second episode i would spend most of the 25 minutes of the episode giggling like a school girl. Absolutely hilarious stuff.