In brief, she was the mother and Regent of
John V. She attempted some power politics, but only wound up causing a civil war which saw her pawn what remained of the crown jewels to
Venice, ship Turkish mercenaries into Europe, and, not to forget, lose power to John (VI) Cantacouzenos.
With her Catholic sympathies - being from Savoy (n.
Italy) she was originally Catholic; her
Italian hangers-on; her fondness for tournaments and assorted other Frankish entertainments; her opposition to St Gregory Palamas; and the stuff up above, you won't be surprised that she was pretty much unanimously loathed by the chroniclers. (In her defence, they're often moonlighting monks - a group she
had particularly strained relations with.)
Amazingly, she wasn't hacked to death, but lived to the ripe old age of about 60.
As to biographies, and
good general lit, that's a whole
thread in and of itself.