Is there a difference between how commissioned officers and enlisted personnel view the UCMJ system?

I would say not all, as many likely never served at all. There are many who were enlisted like Jim Webb, Charlie Rangel, Bob Kerry, among others. Obviously Joni Ernst, Tom Cotton, Duncan Hunter, Lindsey Graham etc were or still are officers.

UCMJ to many seems frustrating, but are likely not looking at Courts Martial but NJP or not even the MCM, rather administrative regulations ala separation chapters.

UCMJ is exactly what it's title said. Uniform Code of Military Justice. It unified and made Uniform, for all branches. Before there were varied Navy (Rocks and Shoals) and Army (Articles of War) systems unhindered by 200 years of progress. Congress needed to emplaced it after WWII and the creation of the USAF in 1947. Coincidentally they use the NDAA to change/implement this stuff. Courts Martial up until WWII were kangaroo courts where ship captains could hang a man with little accountability. Code: it is actually codified. Previous systems were based on tradition and whim. Justice: it introduced appellate processes. UCMJ is based on constitutional law.

The struggle has been: we hold commanders ultimately responsible for everything a unit does or fails to do. Including how their soldiers conduct themselves. Without it, good order and discipline, well, isn't. I have seen allies without real command authority and their commanders do not have sufficient power to command via authority and responsibility. Without command authority, UCMJ is ineffective and we are seconds away from being chimps flinging shit at each other.

People like Kristin Gillebrand don't care about UCMJ, good order and discipline, and Command authority and want to curtail it.

Sure and it morphed between E-1 and O-6. When I first got in, the UCMJ with the "big stick". It was kinda like if you mess with Momma, she'll whoop your butt with that big stick. I was like many junior enlisted. The UCMJ was weaponized and you better not tickle the dragon. Somewhere along the line the UCMJ became a "standard". You can either be on the right or wrong side of that standard. If you're diligent, honest, follow the rules, take care of your shipmates, have a moral compass, etc. you never had to worry about being on the wrong side of that standard. Although the UCMJ is far below The Ten Commandments in precedence, you will see much of the later repeated in the former. If you don't find it, don't worry, Art. 134 makes up for it. If you think of it, the UCMJ can't be legislated to the general population because Art. 134 amongst others would be ruled Unconstitutional (vague, disproportionately applied, and the list goes on). However it's something that helps make the military work. It's both criminal and administrative. So depending on where you are on the food chain, it should mean something different.

As an E-3, I didn't give the UCMJ a second thought. which helped me get into the USCGA. As a Cadet, the UCMJ was discussed extensively in our legal classes. The civilian criminal and civil legal system was also covered. Since the USCG has a military and federal law enforcement power, understanding both systems is vital to the job. As a junior officer, I kept a copy of the Manual of Courts Martial in my stateroom. I wrote search authorizations, conducted Mast (Art 15) investigations, acted in support of the accused and the command, and participated in a SCM and GCM. I was a boarding officer and leader of a custody crew. As a civilian, I have been involved in civil and criminal legal proceedings.

The UCMJ is a great system for the military. More rights and protections are offered by the UCMJ than the multitude of civilian systems. Our command carried out a SCM in one week. It takes months to get a hearing at small claims court. Those who are found guilty the process and punishment are quick and severe compared to a civilian trial. In the "real" world, it takes a lot of effort to be sentenced to jail. In the military, a trip to correctional custody can be fast.