You are very forutunate you have not received a temporary ban from the forums. Especially with all of the negative things you have written about the GMs. As far as I know, if you want to get your warning level reduced you should be nicer to the people who control those levels. You don't bite the hand that feeds you.
In case you have forgotten or are unaware... The HeRO server and forums are run by players who have taken time out of their lives to provide all of us with a positive experience. It's not a business.
You claim to be worried about making suggestions in the future due to a High warning level, I find this hilarious.
"The wicked man fleeth when no one persues." If your future suggestions do not bash another player, and are created with balance and the players in mind, then you shouldn't be worried.