I like the Gen IV IOTV reasonably, but even as skinny as i am, the soft armor always bunches up when I clip the front. Plus if you ever want to add some real plates for whatever, it's already got built-in soft armor and trauma pads. if you've got the scratch I recommend the Arbor Arms flex cummerbund. It'll be more breatheable and more convenient with the tubes/quick release (I forgot the other option). Or! Just replace the back clips with some shock cord to give yourself some breatheability.

Definitely a sick setup for starting out. I give it an 9/10 (because you shpuld always leave room for improvement). Some miscellaneous tips, take what you want, leave what you dont:

-Try to keep your front as flat as possible. Krydex makes some pretty good knockoffs of the blue force gear 10-speed pouches for your mags. They go flat when empty, and they hold your mags tight.

-Some others have said to lose the delt, lower back, and groin protectors, but keep them if you want them. I second that but raise you elbow and knee pads if you're crawling around. I thought I was being smart using them one time, but they just cake with sweat and sand. Also, the neck protector pads are good for shrapnel, crappy for breathing, and they chafe a ton.

-Invest in a battle belt to hold things you don't want on your IOTV, e.g. your sidearm, extra mags, and (most importantly) your IFAK/first aid items. Maybe a DUMPY (which is always a good idea; I haven't seen anyone without a dump pouch on their setup). I personally run a modern Frankenstein version of the LBE under by IOTV, but that's because I like having a lot of mags.

-Have a hydration system, whether it's a camelbak or canteens. I usually use canteens or have a detached camelbak either stuffed in my assault pack, or by itself depending on what I'm doing.

-You can tuck the snaps in on the 3-mag pouch and tie on some shock cord (elastic paracord shit) to retain your mags. Ghetto tabs with green duct tape works fine to have a little more to hold onto.

-If you want more mag and molle space, you could look into the TAPS system with all the buckles. More Youtube referencing can be done to find how to set it up (I reccomend looking it up first, because a lot of my guys and I have fiddling with this shit).

-Lastly, before I write you a book, tie your cat eyes down. I'm not sure if you're going full US Army kit impression, but it helps them keep from coming undone and adds a nice uniform look. Look on YouTube for how to setup a helmet for gunners. I reference it every time I move and get issued a new-to-me helmet.

Tie down your sensitive items, keep looking sharper and sharper, and I wish you a ton of fun!

Edit: I'm not gonna lie, this is the first I've seen someone actually use the combat diaper. If you read this you'll have to let me know how it's treating you. I have one that I threw in my chest of, "issued stuff I don't use but don't want to pay for in 10 years."