I do not actually play the shooters unless I'm introducing someone else to Touhou - most of my 'touhou-time' is spent either reading doujin and listening to music, or playing SWR or 12.3 (I love Meiling's melee style versus everyone elses' potential danmaku-spam styles).
I like Alice because she's a puppetmaster, not because she's tsundere/yandere/whateverdere or bi for Marisa or WHATEVER. Fuggin' Shanghai and Hourai are equally favorite 'characters' for me just because they're puppets.
I'm sure if I met Komachi while she were resting, I'd just nod, thumbs-up, and move along, rather than berate her for slacking off - or joining her. Assuming I'm not a dead spirit.
I like reading up on all the different fan interpretations of the characters and the fanon backstories, just to see how much of it later gets ascended into canon.
The music is one of the primary things that got me hooked on Touhou, followed closely by the huge cast, followed by the crazy numerous doujin circles (Usually, anything by Happy Flame Time is always worth a chuckle or two regardless of how crappy my day has been). Remixes of the music are just about the only thing on my mp3 player, most all of it pulled from the 'Unplugged' playlists on YouTube (current favorite is the Metal version of Green Eyed Jealousy)
I don't see the hate for Aya as a character. Fighting her in SWR, however... that makes me RAEG.
I can seamlessly switch back and forth between keep-away tactics to up-close-and-personal fighting styles with Alice's basic spellcard deck in SWR and 12.3. I learned how because my friend pitched a bitch about me throwing dolls out and running off to let them fight instead of taking risks. He doesn't complain anymore.
I have never successfully beaten any of the shooters, of which I have only two - Imperishable Night and Perfect Cherry Blossom. Since my computer doesn't have the Japanese fonts installed, the one time I managed to burn all my bombs and continues on PCB I couldn't even see any of the kanji on the screen, so I just hit the bomb button to skip the sequence without even seeing the pictures.
While I'd love to learn Japanese for the sake of enjoying mostly Touhou (and some anime in the back), I've never actually gotten started on it.
I see Flandre and Remilia's relationship not as 'Older sister protecting the outside world from crazy younger sister' but rather 'overprotective sister protecting younger sister from world', thus leading to Flandre's naivety.
Sakuya hit puberty, not a pad ad. She's a human, remember, and breast sizes do occasionally make some changes.
I usually only keep track of the new characters from every other game. Not sure why this is.
Reimu is just very bored all the time and can't be motivated to get the momentum to get up and do anything when there's no actual threat, not a lazy poor shrine maiden hell-bent on making a quick buck.
Hur hur I bet no one else has anything like that </sarcasm>
Good lord with that much it'd be hard to find anyone who doesn't have at least one thing in common. Have at ye!