you REALLY have to know what the game is before diving in. They are NOT casual friendly, and they are certainly made with hardcore old school fans in mind.
SaGa games are amazing on paper, but so many of the games are so poorly made and feel like they are coming apart at the seams. Whether it is bad controls (in an rpg, no less), bad character designs, a terrible script, convoluted battle systems, or RNG on everything, there is almost something wrong with every game in the series.
However, I think the Romancing games probably work the best, and the remake of Romancing 2 is actually legit well made.
I also think SaGa Frontier games are interesting, but they are certainly janky and obtuse, and have nonsensical English scripts.
ORAS secret base: http://imgur.com/V9nAVrd
3DS friend code: 0173-1465-1236