To be honest I think people are blowing this a little out of proportion. Sure it has its dangers, like everything else, but as long as you have an idea of what to expect and not an idiot you’d be just fine without a guide.
Wear a life jacket, buzz down the main channel, steer clear of other boats and floating logs. If you want to go above and beyond buy a map where it shows wing dams (hence the drive down the main channel part) and a few community hole fishing locations.
With all that being said, right now isn’t exactly ideal because maneuvering a boat and putting it on and off the trailer can be a challenge with the increasing flow this time of year, like others have mentioned. For practice it wouldn’t hurt to try out Winona for a day to avoid the crowds like you said. Spent my college days down there and there are plenty of fish to be caught.
I think your last paragraph kinda voids the first one. The op asked for opinions and got some good ones…..I think what everyone is just trying to say is be careful, pay attention, and if you are more comfortable going with someone else the first time there are some great guides with years of knowledge out there.