Hey gang playing on here to ask for advice from a very out of practice novice who still owns a D600 and kind of hates it.

I want to upgrade to a camera that fulfils most of these requirements:

• light, the d600 and 850 are chunky as hell so my standards are probably warped
• decent assortment of affordable lenses especially if the used market is good
• shoots 4k 60fps video but will settle for 4k30
• has usbc or hdmi video out for use in livestreaming
• decent photography is a plus
• great software, if the software sucks at least let it be easily hackable

I have some candidates. Lumix DCGH5 mark 1 and the A7 mark 2 are ones I have seen. Looking for other suggestions that fit.

EDIT: changed DSLR to camera to not have "not a DSLR, thats a mirrorless" comments because all I care about are camera recommendations.