I'm a big fan of Shining the Holy Ark. The level design has a lot of interesting gimmicks (like a dungeon where you have to walk on the ceiling or a dungeon where a giant snake blocks your path) & it's a nice change of pace to have a dungeon crawler with premade characters.
Fun fact, according to defunctgames.com, the average review scores at the time (based on the major magazines back then) for the Genesis Phantasy Star games were as follows:
PS2 - 81%
PS3 - 82%
PS4 - 79%
Yep, that's right, the black sheep of the series got the highest average review scores & the game that everyone considers by far the best in the series these days got the lowest.
Here's the Game Informer quote for Phantasy Star 4 (6/10 stars):
"I sat and played this game for about six hours, continually hoping that it would get better. The sorry part is that it never did. Unlike its preceding games, this game goes way too fast. To tell the truth, I will probably play Phantasy Star III, quite possibly, Shining Force II more than PS IV." -Ross, The Rebel Gamer