Ian,
My suggestion will be more related to design, rather than brand-specific.
Whenever I choose lower-half cycling outer wear, I consider my padded lycra shorts as my base layer.
Anything longer goes "over" the shorts so it can be added or removed as I warm up, cool down, or as temperatures change.
Because none of these "overtrousers" are padded, I find brand doesn't matter so much as long as they include my desired waist drawstring and silicone gripper elastic at the hem so they don't ride up. I also like a design that raises higher in the back so they don't slip down as I pedal.
Keeping my padded lycra shorts as my base layer means I don't need a changing room. One time in Bulgaria on a very cool 38°F/3.3°C morning, I warmed up enough to lean my bike against a courtyard wall in a small village while I began to peel off layers. It took awhile because it had just rained, I was standing in mud, and I didn't want to get my socks muddy as i removed long tights and the 3/4 tights above my shorts. An old lady at the farm across the road had been observing the process with great interest, but disappeared briefly after the tights came off but before the 3/4 tights left. She returned with a nicely proffered bath towel and a sweet smile, apparently figuring it was all coming off!
In a related topic, I have sometimes used a blanket pin to make a wrap-skirt or kilt out of my camp towel when no changing room is available. It works well to retain modesty if other cover is unavailable, as the shorts can be slipped off or on beneath the towel.
Ian, if you go for the bib-top 3/4 tights, please tell me how you successfully negotiate toilet stops in rainstorms. I have largely given up on bibs (including my otherwise highly recommended Pearl Izumis) after one too many "natural breaks" in winter rain. Off comes the rain jacket, then the thermal jersey, then the base jersey, then the straps before business can commence. Then, the whole rain-sodden lot goes back on a cold and shivering Danneaux. Surely there's a better way with bibs? Putting the straps over all but the rain jacket has been my preferred solution to date, but the jacket still has to go. Seems like a lot of fuss compared to my preferred bibless style shorts/tights with waist drawstring.
All the best,
Dan.