As DELee already pointed out there are active Marriott Lurkers on this forum. They do take DM's (Private Messages in FT speak). I have had good luck working with them in the past when I had an issue to be resolved.

Please don't take this the wrong way, when you state you have a "double handful of complaints" and don't elaborate further on the them, it is suspect. E.g. if you're a chronic complainer (Marriott can and does track customer complaint history), you're unlikely to get satisfaction no matter what level of Marriott representative or executive you contact. On the other hand, if you have just had a recent run of bad experiences and want to discuss them with the appropriate empowered Marriott representative, that is different. Providing some detail on the nature of your complaints on FlyerTalk would enable the community to provide more assistance and guidance. Regardless hope you are able to resolve your issues in a manner that is satisfactory to you.

--Jon