it is really depends but i do not do float hunt like you guys more a river hunt i use different pants under wader if needed up to wool ones depending on the waether and temperatures. seems you re alreeady set up.
enjoy the hunt,
I also pack Simms waders and KUIU Axis pants when I head out to Bethel. You are going to be just fine with the side zip-vents on the Axis pants when wearing them in the field...BTW, I don't wear my Axis pants under my waders...they are with me if I actually get a chance to hunt without wearing my waders LOL.
You may likely be in waders all day, so be also thinking about what you are going to be wearing under your waders. For example, I have a base layer (and a 2nd pair back-up), and an additional layer I can add under the waders as needed, e.g., lite-weight fleece pants.
The best to you for a safe and wonderful adventure...I head out there next Saturday, and just shipped gear out there today!