new track master revolution mods

If you search the forums you'll see a number of threads discussing the differences between revolutions track and what we call blue tracks (i.e. original PlaRail). Most discuss around the design of the revolutions system and the fact that effectively most sets are almost 'one-trick pony' type sets. What we mean is that it will do something fancy, but that's about its limit, when you want to expand it's difficult to utilise all the parts as the sets have so many dedicated parts that only do one thing. The best comparison is original lego which had lots of generic parts and fostered childrens imagination to build things and new lego where you buy a kit for say an X-Wing fighter which can't really make much else and takes away that imagination/education element that the original gave you.

So to a degree it depends what you want. Do you want something that out of the box is impressive but gets boring quickly, or something that on the surface seems less exciting, but over time grows and keeps a childs interest as they add new features and functions to a basic set?

One other thing that has not been mentioned in this thread yet is that the new recolutions engines have been deliberately designed by Fisher Price to not run perfectly on the older blue track. This can be addressed with the judicious use of a file (again threads on this can be found). But it is a bit of an issue for anyone who doesn't like modifying engines and is really a cheap shot to try to lock people into the revolutions system.

As for your desires to up the voltage in your loco's to get more speed have you considered fitting a voltage step up circuit? You can use these to take the basic 3v and step it up without the use of extra batteries. No doubt this would have a downside in terms of battery life, but it is maybe an easier mod if you have the space