Dan,
You asked whether I take anything besides Requip for PD ... No, I don't.
You asked why I increased (good question) ... I was on 12 mg Requip for 2-3 years. I tend to wait 'too long' before increasing my meds/Requip. I increased Requip because my symptoms worsened to a point where it bothered me enough to make the change. My tremor was worse. I was having some slowness of movement - an issue at work when I try to click on that ever-decreasing-in-size (or so it seems) check box.
I work in the Information Technology field whereby I am on a PC all day. I am a database administrator and under a lot of pressure at times. The more significant the issue, the more the tremor. I can definitely tell my symptoms are aggravated as the stress increases.
Early on I told folks at work about my PD. Hiding it was aggravating my symptoms. I thought a couple of folks knew and had noticed my tremor. After making it public, I asked folks whether they had noticed. Not one person said they had (can't say the same today).
OK ... more than you asked for. Requip has worked well for me. Side effects have been minimal. I have NOT had a significant issue with drowsiness - certainly something to be aware of and address.