+1 for the Zenkaikon suggestion, the venue this year is going to be awesome, and there are a lot of nearby attractions as well. (plus I'll be there, and that's an instant increase of 30% awesome; you'll be able to find me running around wearing a staff shirt.) I don't know all that much about Homestuck, I just know that last year's Zenkaikon had a pretty big showing of Homestuck fans (literally couldn't look in any direction without seeing at least one). There's definitely going to be Homestuck fans there this year, though I've no idea how many.
Wizard World Comic Con is always pretty big, and right in the middle of Philly, so it's super-easy to get to.
The other suggestion is to look into traveling a bit; there's a bunch of conventions that set up home in Maryland, which isn't a long trip at all (I believe Amtrak can get you to most of them, and there's of course the buses; if you're younger though, you might have a parent going with you anyway, so it's not a long drive from the Philadelphia area. Katsucon is coming up in two weeks, in National Harbor MD; there's also Otakon later this year, which should be in Baltimore (and though I've never been, I hear it's worth the trip).
Best of luck! WWCC is a pretty awesome con, from what I've seen of it (I've only ever been to the WWCC in NYC, and I was on-staff for something in another room so I barely got to see the main floor). Plenty of my friends tell me the one in Philly was great.
Zenkaikon moved to Lancaster, accessible by train, ample paid parking on site. Not my style, but if it's yours, more power to you.
Within a 10 minute walk are dozens of restaraunts from a variety of styles and nationalities, as well as the infamous Village Bar and Chameleon Club for live music. Come for the Amish, stay for everything else.
There's Philadelphia Comic Con. There's plenty more cons too, I'll have to ask around since I don't remember. I'm not from there but many of my colleagues are and if you're heavy into comic books there's quite a bit going on in Philly.