The cost of the XTR display that I posted the picture of on our bike is $79 on the web and does all you want. The d-fly is a ant transmitting unit , cost is $55 plus a cable then you need a Garmin unit to talk to for an additional $350-500. You can get a very simple Garmin for the other data for much less. I doubt that your outer chain ring position is wrong. It is more of a function of the large difference in diameters of the two chainring setup. You might be able to do some tweeting to allow it to only be a problem in the 2 smallest cogs. However there is really no reason to be in those combinations and would allow for a lot of chain slack.