A RPG is not only about the battle system. It's a combination of plot, environment and finally battle system.
What you guys are complaining about are games that existed on the SNES. Current SMT titles by far do NOT have a high encounter rate.
SMT is release in 1992, 13 years ago. SMT:If is released in 1994, 11 years ago. Persona in 1996, 9 years ago.
The original Japanese version of Persona is probably the last "high encounter" SMT game in the line. I don't recall SMT3: Nocture Maniacs or DSS having that high an encounter rate.
SMT is one of the first RPG I played that has encounter influencing items and as I had mentioned before, they last for a good duration.
There is only 1 main character for SMT, which is you, the hero who somehow came across an ability to summon monster. The hero is a one man army fighting against heaven or hell to put the plot in ultra simplistic terms. Last I check, the image of hell is a place full of demons and the likes. Think of it as a corrupted version of Pokemon
There isn't any unimportant guy, it is just you, your bunch of demons vs the entire world.
SMT has off hand 2 kinds of physical attack (Guns/Melee), 10 kinds magic attacks (Fire, cold, wind, lightning, earth, holy, curse, nerve, mind, almighty) and 3 kinds of support (healing, buff, debuff).
Monsters can be weak, immune or absorb any attack forms. In SMT it is far from trivial to recover everything before the boss and boss fight are challenging and tactics work since buff/debuffs actually mean something, along with the different avenues of attack.
You don't gain much abilities by fighting. SMT has always being about talking with demons and forming contracts etc with them. Sort of like Pokemon I guess.... You collect demons, fuses them up to make new demons, which is where the bulk of spells etc come from. Battles pretty much just levels your main character so that he can summon more powerful stuff, while hiding in a corner.
As Tort has mentioned, it is not a series for everyone. It is targeted at a very cliche market even in Japan. If you like games with a good plot about the occult, in a modern day setting or like dungeon exploration, SMT is suitable, else, ignore the first few games. SMT3 onwards are more for the general RPG player.
I play SMT mainly for its plot and the Persona line has one of the best music in any RPGs, creating an enjoying atmosphere to me.
君は夢で泳いでる人魚になれたから
深く沈んだ思いを 集めて星へ
君は夢で泳いでる人魚になれたから
涙枯らして歌うよ
報われるように
報われるように
夢で会いましょう