I think infantry modernization is difficult to achieve as there's often a huge gap between ideals or goals versus what people can practically do in a wartime situation. Passing down lots of sensors, networking, etc to the common soldier sounds great in theory during peacetime. However, in wartime, chaos ensues and the thing that matters most, IMO, is rapid, out-of-the-box thinking. In other words, education and skills matter more than gearing up.
That being said, I think there are a few low-hanging fruits the Army could leverage for the benefit of soldiers, i.e: (1) scalable-plate carriers; (2) assault rifle scopes, sights and grips; (3) individual comms gear; and -- maybe -- (4) an advanced sight with miniature ballistic computer. However, I think (4) would likely be more valuable paired with RPG-7s than with assault rifles. Still, some units (like marksmen) could benefit from it too.
However, I'd put more emphasis on building skills and critical thinking.
Otherwise, I think the next big area of growth is network-enabled warfare. It'll be interesting to see how the PA is linking infantry up to the wider system. I remember Western concepts from the early 2000s that tried giving infantry mini-computers. That was a huge deal and the most expensive component of the suite. Ironically, that input could be relatively trivial now as you'd just need a ruggedized smartphone (albeit with some key mods) to get mapping, info management, etc, into the hands of a soldier.