6.4, yes I'd stick with it even if the current electric vehicles ran circles around me. If anything less performance than 6.4, say less than 450 hp., then no. But even then, the electric 'revolution' in its current(pun intended) format is not for me and for reasons previously mentioned.
If Mopar was to make a V-8 with less performance than the 6.4, I'd take the new I6 and be content. And based upon your comments it having more room modification/improvements. If Mopar made a V-8 with same or more performance, and was around same price as today's LX's , then yes, I'd stick with it.
No wish to start a riot, but I once owned no less than three versions of the '86-'87 Buick v-6 Turbo cars. I spent less than $25 and took it from 9.60's to 7.70's at local the eight-mile drag-strip(the ''receipt' to do this was at one time all over the internet; I also took it down National Trails Raceway with 12.38, 12.39 and 12.40 e.t's at 108-109 mph. Was mostly off the line power spooling the turbo up.
And, yes, I've had Mopars in the past as well that I loved and miss now.