I'd say before there can be hand reading you need:

1) a solid idea of what types of hands different types of players play from various positions

2) board texture analysis and understanding the "standard" lines for various hand types

3) understanding of how different hand ranges interact with different board textures

A hand reading series would be great, but I think for beginners it would be useful to have structured material on 1 and 2 first.  Some other sites have this, but RIO doesn't.  3 is sort of difficult to grasp as a beginner, but very useful.

That said, I think the most effective way to learn hand reading is to put in tons of hands at the tables  :)

Also, when playing lower limits hand reading is less useful because players often really have no clue about what to play from where, so they can show up with all kinds of weird hands.  Even the nits who play very tight from UTG show up with some incredibly strange hands sometimes.  They also tend to not understand that they need to fold bottom two pair when facing a turn shove on a straight card, so knowing that they can't have the straight and bluffing with blockers+equity is only marginally useful.  Learning to play simple straightforward standard lines is way more valuable until you get well into the mid stakes.  (not sure what stakes OP plays so this is more of a general comment)

I play very low stakes and agree that understanding what kind of hands people play from different positions and knowing the std lines are the basis for winning at lower stakes. A PLO series that outlined those ideas would be awesome.