If you're looking for a logo, try
FP's graphic shop section. They might be able to help you out.
In terms of your site though...
I think having more content visible to guests would probably be a good start. I mean right now you have 8 forums. 6 of them are marked "protected". Meaning guests can see these forums exist, but can't see anything inside them.
The only sections that are visible are the introduction and suggestion sections.
And not to be rude, but most guests aren't going to care about introductions or suggestions. So you're not showing them things they want, nor are you giving them any sort of reason to stick around.
If anything, I'd make both those section you have currently visible to guests, visible to members only because there's no real reason guests need to see them. Guests probably aren't going to care about making suggestions to your forum and it's possible that a suggestion section (especially with a long list of suggestion topics) may actually cause them to leave thinking your forum either needs a ton of work and/or you're really slow implementing suggestions.
Also, what type of site are you running? Since it seems like you're more of a gaming site than anything (since you have 2 forums for console games and then another forum for forum games).
If you are mainly a gaming site then you probably will want to add a section for Nintendo. This way you're at least covering the big 3. Then later down the road, after you get more activity, you can expand with a section for PC gaming too.
But if you're not a game site you may want to combine the Xbox and Playstation game sections into one forum (maybe just call it "Videogames"?) And then use the leftover forum to become a TV/Movie section.
For the theme, I agree with Scribbler397 here that when I hear the name Talking Seed I expect a green theme. And I think that it would be so much nicer to have a darker green theme rather than a red theme for your site. (Possibly a theme using #395D33 or #2F4F2F as the main green colour?)
I don't know who handles themes for IPB on FP, but it'd be worth asking about in a topic in FP's graphic section also (if/when you go to ask for a logo).