Goodness no, you certainly didn't make a mistake! I've stayed comped in the Forum Tower rooms twice and they are very nice! Take a look at the pics on their website, the photos are exactly what the room looks like, unlike many of the hotels who "spruce up" the pics to make the rooms look better.
There are 2 robes in each room, a tv in the bathroom mirror, big flat screen tv. Views from this tower aren't great and the windows are small. I really liked the dark decor myself.
I was diamond my next trip and they automatically upgraded me to the Augustus tower. Those rooms were larger with a jetted tub (which I could never get to work BTW) and the decor was lighter. If they hadn't already upgraded me, I would have happily stayed in the Forum Tower again. If you are diamond, they will probably upgrade you prior to arrival, but don't sweat it if they don't, it's a really nice room.
I've not stayed at PHo, but have stayed at Paris in a Red Room several times and the Forum tower rooms would be very comparable to a red room. One thing I really liked about Caesars is the people who stay there..... all my stays have been very quiet. I love staying at the Flamingo but the one thing I hate is all the young partiers who come in at all hours screaming in the hallway. It can, and does, happen at Caesars, but I think you have a better chance of people who understand how you act in a nice hotel.
So, just look forward to your stay in a great property comped and enjoy!
diane