Part of my plan to play through Might & Magic, DQ, and FF (cycling through the 1's, then 2's, etc.)
I've beaten it a couple times on NES, so I decided to knock it out on GB. I played it on SNES via Super GameBoy. Unfortunately, they used all the same border graphics, except for one, as DW 1, so the "nifty" factor wasn't there.
Definitely a large step forward compared to DW 1 with the addition of two companions and a much larger world (an extremely simplified version of the DW 1 world takes up about 10% of DW 2's world). Introduced the game of chance, which is in every subsequent installment.
This has one of the smartest, if not THE smartest, AIs for round-based RPGs (where you input everyone's commands at the start of each round) of all the games with this battle system that I've played. It actually competently decides which enemy to attack the vast majority of the time.
As with DW 1, I didn't find myself needing to grind very much - almost all of my grinding was near the end. Took me about 15 hrs to beat, about 2-3 times as long as it took me to beat DW 1.