Living in the now moment has little to do with time, believe it or not.
The Eternal Now Moment is not like a really long time - it is more like the absence of time.
It is more like "an awareness" within which time and space and etc "take place"...
Relative Ideas like past and future should not really be confused with Absolute Ideas like Now, or "living in the moment".
Absolute Ideas are, to me, best not discussed as though they have "opposing sides", or "either/or sides" - as though the past and present conflict with each other. (Remember, there are no conflicts in the Absolute...)
That being said, of course it is a wonderfully fun Relative Life Experience to learn more Now about our past lives, and we can even look into our future lives Now if we choose. It is not necessary, but certainly an option to place one's focus Now intently on past or future lives.
We wrote about the idea of Exchanging Gifts below, and this reminds us of that.
It is totally cool to Exchange Our Gifts of Time, Talent, Love and whatever else we perceive Life's Gifts to be for further knowledge of things we have already done, or may do one day.
In the same way it is fun to Exchange Our Gifts so we can explore a foreign language, or how to better pilot a racing motorcyle, or take "better" photos. Simply because one enjoys these things, and wishes to know and experience more about them.
All of these are things we do and experience in Relativity. That, to us, is Life!!
Robert Monroe wrote great books on out of body experience, and the direct, conscious exploration of past and future lives, and that "spirit family" concept you mention he also touches on. The Monroe Institute is near where we live, although we have never visited - but we have read many of his books and experienced a great deal of that which he discusses - great, great stuff, and wildly fun!
Finally, some Now find that their deepest most directly rewarding Relative Life Experience is to delve deeply into the Absolute Experience of the Eternal Now Moment.
This would be to focus our Now Gifts on the Now Moment of the Now Life. Not better, just another way.
This arguably, theoretically, merges the Relative and Absolute perspectives - the Relative is observing the Absolute, and the Absolute observing the Relative. Sort of "locking eyes with The One as one goes through the day".
Often some sort of transcendent thing is reportedly experienced.
Alice & Greg