Other than the fact that the 1dx is full frame, how is it more akin to the 5d3? The 1dx is a sports, action and wildlife camera and so is the 7d2...
When I say I wouldn't mind a 5d3, I mean as well as my 70d or a 7d2. It wouldn't fill all my needs but it would be nice to have
Not sure why you're classing the 1DX as a "sports, action & wildlife" camera to be honest. Personally I think the days of pigeon-holing cameras like that are over now. There are vast numbers of photographers using the 1DX for all manner of wedding, portrait & landscape photography.
The 1DX is the ultimate Canon body for anyone who doesn't need the crop factor of an APS-C sensor. If you do need the crop then the 7D2 is the best option, otherwise the 1DX is a better bet. If anything, what you call "sports, action & wildlife" photography is more likely to be the type of shooting that would benefit from the crop factor and thus the 1DX may actually be less suited than the 7D2.
You're right in that I was saying the 1DX is more akin to the 5D3 than the 7D2 simply because they're both full frame. Yes, there are features the 1DX shares with the 5D3 and features it shares with the 7D2 but, for me personally, the sensor format "defines" a camera more than any other feature so the fact that the 5D3 and 1DX are both full frame makes them far more "similar" than the 1DX and 7D2.
I guess it all depends on personal priorities. You've said the 7D2 is the best option for you right now but the question is why you feel this way. If it's because the crop factor gives you more reach for wildlife and so forth then doesn't that rule out the 1DX as a future upgrade path? If the 1DX is a viable future path then you're effectively saying that the crop factor isn't the "be all and end all", in which case why not move to full frame and side-step the 7D2 altogether.
Basically, I'd take a 5D3 over a 7D2 any day of the week. Yes, the 7D2 may have slightly better AF, a higher frame rate and other features which the 5D3 lacks but for me none of that would matter. Unless I actually needed the crop factor I'd go full frame every time