I plan to jump from DSLR's to the R5 / RF lenses once the new gear is released. I love the fact that I can use my EF lenses with the M, EF and new R cameras. As I look at my gear strategy moving forward, I plan to eliminate DSLR EF bodies and eventually EF lenses. I use the M as a small backup to my EF system and this has worked very well. It gives me the option to have a small travel body with small, light lenses AND the ability to adapt to the EF system as a backup. I would really like a robust M5? (m6 II minimum spec, slightly larger body, grip option, weather sealing, HIGH REFRESH RATE EVF, etc.) that continue in that backup role and provide a more compact system when I want to travel light. The problem is that I can't have one set of hight quality lenses that can be used by both the R & M bodies. Bottom line is that I would prefer M move to an RF mount or give me an for RF to M mount so I can share lenses. I would be really happy to see the Canon equivalent of a Fuji X-T4 especially if they could give me some way to use the RF lenses. Think M5 II + RF 100-500 (160-800) when I need the reach.
I know, I can dream.
I generally agree.
Anyone that asks me about buying 'serious' camera gear now can't believe it when I recommend 2nd hand mirrorless to them. I don't recommend DSLRs now to anyone who is not thinking of 'going pro' (and there are plenty of Pros now that are working just fine with mirrorless cameras.)
However, you already have a set of high quality lenses that work with R and M and that's EF lenses
For kit lens, I use either an 18-55 or a 17-40L (speedboosted where appropriate) depending on where i am going and a 70-300 for zoom. Whack a teleconverter on there and you've got your 700mm lens. There's perfect coverage from 19mm - 672mm with 2 lenses.
Seriously though, the EF lenses are the most adaptable and flexible of the lot - I don't think you will save a huge amount of weight or space moving EF over to R. What I can guarantee you is you will spend a huge amount of money. What I will do at some point is buy an R body when they are reasonably priced and add it to the above travel kit!