I've been without my PS2 for awhile now until a couple of days ago when I got it back. As I looked at my old PS2 library I started thinking about which of these old series I miss the most and wish someone, ANYONE would revive.
The first is my favorite JRPG series, Suikoden. I've played III, IV, and V multiple times and still enjoy them (that's right, someone enjoyed IV lol). The first Suikoden isn't that bad either even though it's an old PS1 game. I think there's a lot left to be explored in the world of Suikoden. Suikoden V introduced the southern continent with the Queendom of Falena but the New Armes Kingdom and Nagarea Theocracy are still left unexplored. Even some places addressed in other games are still largely left alone, Camaro Free Knights, Zexen Confederacy, Gaien Dukedom and even the Holy Harmonia Kingdom are mostly left alone. There's probably even more that could be done with the lore of Suikoden. I always loved the turn-based combat and the way it was setup in pairs (or formations in V). The strategic battles (Naval battles in IV or RTS battles in V) were always a fun way to break up the gameplay sequences. The games always had a cool cast of characters with the 108 Stars of Destiny and it was always enjoyable to try and recruit them all. I just wish Konami hadn't abandoned the series after V (and don't you dare count Tierkreis, that doesn't count even though it was a pretty good RPG on the DS). I wish it'd come back but have literally zero expectations of it happening...(Here's a cool map of the Suikoden world http://images.ngamexp.com/6/0000006093.jpg)
The next series' is Dynasty Tactics and Kessen. Or rather, I wish Koei would get back to it's roots with historical strategy games set during the Three Kingdoms Era in China or Warring States Period in Japan. Dynasty Tactics is like chess on steroids, cocaine, and also jacked up on energy drinks. There's so much strategy in the games, trying to setup Tactic Combos require a lot of foresight and one little slip-up throws everything awry. Kessen is an even better strategy series from Koei, especially with the first and second games. (The third game was only strategy in name, it was a lot more like an action game than anything else. Still wasn't a terrible game though). I've spent so much time playing through the two games with their cool setting and strong real-time strategy gameplay. Unfortunately Tecmo-Koei is only interested in action games now with multiple Musou series now (Shin Sangoku, Sengoku, Kaizoku, and Hokuto) and games like Ninja Gaiden.
The next is Onimusha which personally I always thought was cooler than DMC. I don't know if it was the setting (I don't think it was because I really like 3 which was partially set in France). It was a little more strategic which was something that I really liked about it. The games were just a lot of fun and combat was varied with the different weapons your characters had. I didn't really get into Dawn of Dreams but I think I didn't really give it much of a chance back in the day and want to play it again soon. For some reason I actually think Capcom could bring the series back. They always seem to be doing crazy things that I wasn't really expecting lol
The others aren't really series I would like to see brought back but are games that I wish would have gotten a sequel of some sort. The first is MS Saga which is a Gundam RPG. The game itself really wasn't anything that special and I doubt if many people even took notice of it's existence at the time. The thing I truly love about the game is the customization involved in equipping the Mobile Suits for the characters. The story and combat could've been improved (a lot) but an RPG with Mobile Suits was a really cool idea for me.
Another game is Legaia 2 Duel Saga. I don't know how many of you played the game but it had one of the most inventive battle systems I've ever seen. Fighting wasn't just "Attack" or "Magic -> Fire" or whatever. You fought with directional button inputs and stringing together a chain of attacks. So an attack would be like "Down, Up, Left, Left, Up, Right" and you'd attack six times in the corresponding directions. Beyond that you couldn't use "Up" attacks on short enemies or "Down" attacks on flying enemies. Along with that the game included Arts which were used by putting together certain chains of attacks (and no, you didn't have to memorize any of them). It was such an interesting battle system with some really intense/epic boss battles. It was a really awesome RPG that I only finished recently and I'd love to see another game with the same combat.
Feel free to share some of the series you miss from back in the day or whatever if you want :)