Well, first suite availability is irrelevent with elite status upgrades. If the hotel doesn't want to upgrade you to a suite room (Jr or otherwise) they are perfectly within the rules of the Marriott program. This is because suite upgrades are specifically excluded from the elite upgrade benefit. Though I would say I much prefer the hotel staff just saying that they have a policy of not upgrading elites to suite rooms rather than saying they aren't available.

As for the CL floor, I really couldn't care less about getting on the floor or not. The big issue is making sure I get access to the CL itself. As long as I have that, I'm usually happy. Though again, if the hotel does have rooms on the CL and you want one, I can't see why they wouldn't upgrade you. You might ask to speak with the GM to see why you see CL rooms available but the hotel staff didn't want to upgrade you to one of those rooms.

With all of this, don't think these types of "issues" are just with Marriotts. I'm typing this from a Starwood hotel right now. They did upgrade me to an ocean front room, but not to one of their suites. They stated that all the suites were booked up when I checked in. But when I check online, I could book multiple suite rooms if I wanted to. So they do have them, they just didn't want to upgrade me. I guess I could push the issue with the GM as well, but in all fairness, getting an ocean front room was good enough to make me happy. (Yes, the suite room might have been a little better, but not enough to make an issue of it.)