To LOVE-Ru, Kemeko Deluxe! Recommendations
They both have a strange, space girl and similar situations and characters, if you liked one, you'll like the other for sure.
Both has similar lead girls and males. also, both has a similar feel to it while you are watching.
Both include unwanted pink-haired wife that gradually becomes more important to the main character. same style of wacky comedy and fan service is almost equal. both have open endindings.