Mark - I would maybe experiment with 1 or 2 games first. Maybe try very popular titles like Halo and Call of Duty. As for being different, from what I see in the Destiny LFG it's extremely basic. Post auto delete I believe after 10 minutes. If you list your guardian you can edit and update and it goes back to the top. Saving your information is nice as well.
It shows the most essential's needed - Console - Gamertag / PSN - Level - Light - What Activity You Are Looking For - Comments - Language - LFG / LFM (Looking for Group / Looking for More)
This being a basic Destiny LFG source.
From my experience using it, it sometimes freezes. An Idea that I would like to see added or changed would have to be a message icon on that post. It would read the console and Gamertag so that it sends the message to the right player - open in a small dialog box and send a message to that player looking for group or more for a invite. Something like that is super simple, the domain lookup might be the killer part. It wouldn't be as easy as just typing DestinyLFG and post your guardian etc.
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Oh anyways, Got my Hunter to 334 light, ran King's Fall Hard Mode raid 2x now. Trying to re-establish my Warlock whom I left in the dark. Was going to just create a 3rd Hunter, but decided to keep my Warlock even though I deleted all my better gear. Luckily I have 335 gear I can infuse once I get something good dropped - Other than that nothing much else.