Skeleton Mages - Advise on Progression or Change Build?

This is my first time playing Skeleton Mages. I really like it. The only drawback is the slow walking speed, which can be upgraded to rare boots, but sacrificing +1 skele.

My current POB: https://pobb.in/_CvgZDJ-skid

My build is nowhere great, but at 9 mil dps, 15 mil with Vaal it serves my purpose so far. I believe I have only spent less than 20 ex. I'm doing Logbooks + Grand Design Atlas focusing on Expedition juiced with Sentinels. Nice currency. I guess I want to try most content including sim 30.

I'm unsure on the next major progression. I'm very frugal spender, upgrading only when necessary to do my content. I know the ceiling of skelemages is pretty high but unsure at what point it gets too expensive. I feel I want to push further, but not sure if I should keep doing it on the skelemages or switch to other build.

Any advise would be great. There's still missing increased minion damage on my wand. I need to get +L20 minion life to my helmet (not going for the pseudo 6/7L). I can also do +2 to my Fleshcrafter etc. I need to improve my chaos res so I can take off 3 points from my tree. There's also melding build with 90% res.

I also don't know if I should stick to Life hybrid or switch to full CI.

My question, is it worth it to keep pushing dps and survivability on my skele mages? I don't have a lot of time, I'm scared I won't have enough exalted to push it to where I want it to be. I currently have close to 40 ex. I researched CoC FR, it is definitely out of budget. 80 ex to be comfy and definitely benefit a lot from MB. So 250ex.

So I guess best progression that is best dps + tankiness per chaos value.