Here is the thing: normal enemies were designed to scale to match your level in most of the SaGa games. Most SaGa games utilize a mechanic called Battle Rank; in short, the more enemies you fight, the more powerful the enemies you fight become. Each dungeon is populated with enemy symbols that correspond to various different species of monster. For example, the fairy symbol corresponds to Mystic-type enemies. When you touch an enemy symbol and enter battle, the game cross-references the race of the enemy symbol and your battle rank, then generates the corresponding monster. Then, the rest of the enemy party is fleshed out based on your Battle Rank.
In other words, in SaGa games such as the Romancing SaGa games and SaGa Frontier, it is literally impossible to run into regular opponents that are not appropriately matched in strength to your party. Of course, there are things that modify this. For example, the Shrike Bio-Lab in SaGa Frontier is designed such that every encounter that takes place there is always a few Ranks higher in power than the party's Battle Rank. At low levels that means fairly tough lizard-men. At high levels, it means hideously powerful Dullahans.
The net effect of this is that for the most part, the game doesn't place any limits on where the player can go. No matter what dungeon you explore, then enemies will always be of an appropriate strength (even if that means that they might be fairly challenging).
The only catch is that fixed enemies, such as bosses, don't scale with level. It is entirely possible to waltz through a dungeon fighting familiar enemies until you suddenly run into a boss that wipes your party off the map. Fortunately, this is a rather unusual occurrence. Most powerful bosses are found either in plot dungeons, where you need to progress through the plot at an appropriate pace in order to open the area up, or in sidequests that have some conditions to unlock. There are exceptions of course, but it is pretty easy to figure out what bosses are fightable or not through a little trial and error.
I find the SaGa series' approach to enemy scaling to be quite liberating. It is a necessary part of having game design that is so open-ended.