NHK ni Youkoso!, Ore no Imouto ga Konnani Kawaii Wake ga Nai Recommendations
Embracing the otaku culture, having life counseling, and other crazy stuff. OreImo just faces more on the girly romance side while NHK ni Youkoso tackles things that a hikkikomori does and what they think are true "conspiracies".
Ore no Imouto => Welcome to the NHK
Both have Otaku issues integrated and dealt in the story. While OreImo is more light and focus more in the setting, NHK has a more psychological, personal and dark takes.
They both deal with "otaku" culture. However, OreImo is more on the humorous and light side, while Welcome to the NHK! is darker and more realistic. Both are comedic, though.
1. Otaku facing society.
2. Involves counseling or helping out one another.
(Note: WTT NHK is darker and more realistic than Oreimo.)
Both reference otaku culture a lot and involve the character getting help and counseling. OreImo is definitely more light and NHK is more psychological. They both are pretty funny though, if you like otaku humor.