How to Make Your Role Playing Game Enjoyable

Have a sense of scope. Know what's within your boundaries and go for it. Don't rush your product but at the same time don't take forever on miscellaneous details. Plan it out and stop halfway through and re-assess what you can and can't afford to do.

Storyline: It's why we're here. If you aren't making an open-world RPG pay careful attention to your storyline. Find ways to make it deeper and interactive as often as you can. Sometimes a great storyline can save an RPG with so-so gameplay. On the other hand, a bad storyline can kill an RPG with outstanding gameplay. This is what the player is going to be following for some ~20-80 hours of their life. If they don't like the story in the slightest bit, they will drop it within the first couple of hours.

Allow some freedom. Yes, even in the most linear of RPGs you need to have sidequests and optional dungeons and bosses. Players like to explore and take on new challenges. Don't be the one to deny them that.

Create an atmosphere. It is fine if a game's setting, mood, and so on so forth, is foreign to the player but make sure it fits and is crafted carefully. A lack of atmosphere can make the player feel disembodied from the story and a broken one can destroy immersion and ruin a perfectly good story for the audience. When done right, your game can do just the opposite and draw the audience in.

Think about choice. Even if you don't make a game with branching dialogue options or multiple endings, it is still good to consider choice and imagine where it might fit into the game. This helps you look at the story from the player's perspective and not just the character's. Are players really going to like the new NPC you introduced even if he's on their side? If not, don't make the party constantly take actions to keep that NPC in the spotlight, or have a character with an unfriendly disposition interact a little more with the NPC than others to give some satisfaction back to the player.

Look into end game content. It's kind of like the cherry on top. If the player is able to explore and find more challenges to take on they will applaud you all the more for it. On top of that, it keeps players engaged with your game after the climactic showdown with the big baddie. This will make them more likely to spread the word about your game or replay it at a later date.

Balance everything. If players have to consistently grind at certain parts of the game to stay on par then something is wrong.

Focus on the core. Usually the core gameplay of simple RPGs is combat but regardless of what your core gameplay is, make sure it holds up and stays varied within its bounds. For instance if you use a quest system as well. Make sure to vary the quests available and keep them interesting.

Don't create n-Dimensional characters. Most original characters have the issue of being n-sided. No matter how many characteristics you add, the character will always feel lacking in some areas and too opinionated in others. Realistically, a character has an infinite number of faucets to their personality but it is understandable if that is hard to accomplish. Rather, pick a theme for the character and work from there.

Meddle with the MC. Let the player create their own character or make them a silent protagonist. In the end, the main character probably won't be leaving the player's sight, so make sure it is someone they like.

Juxtaposition is key. A dark sorrowful story can't stay that way for too long and realistically no character is able to stay so depressed for so long without doing something drastic. Show that they are still human without killing the atmosphere.

Angst is fine if justified. The main issue with angsty characters in RPGs these days is that most don't have much to be angsty about or perhaps the source of their emotional tension isn't addressed or expressed well. Keep their motivations personal and their angst justified and expressed properly and the player will at the very least show some respect for them.

Work with a radiant AI. If you don't understand radiant AI, here is an example: you have an easy quest you forgot to complete in one of the earlier towns and you want to finish it off. As you backtrack the enemies are scaled to your level in order to keep the quest relevant at this stage of the game. This isn't necessary in every RPG but it works wonders in larger, open-exploration ones such as Final Fantasy XII (it's radiant AI would be the LP you gain from killing wolves in the Estersand) where backtracking is inevitable.

Try using Easter eggs. These aren't really necessary but they are often fun to find and digest. At least they let the player know that you had some fun making the game and put your heart into it.

Make the main villain active. If the main villain doesn't react to the player characters or even recognize their existence then there's something wrong. Inactivity needs to be explained and major events need a response, however small they may be. The main villain is, in the end, a character too.

Have minor villains too. This goes without saying. The smaller story arcs that span from town to town need an antagonist obviously. Make sure they aren't just token characters though.

Use a thematic soundtrack. Create one yourself if you can, just make sure the basic tune can portray the story's main themes.

Make your world active by creating events. Optional sidequests that pop up in revisited towns are a basic example of this. Others can be tied to the main storyline such as a dragon flying from the cave you just exited to attack the party's hometown. Or maybe something as subtle as changing most of the NPCs' dialogue in a given town after a short cutscene in a different town. Mix it up and come up with some of your own.

Keep the character's motivations personal. Saving the world is wonderful but ask yourself if that kind of plot device is really necessary. If the characters would not fight the final boss if it wasn't going to destroy the world then you should probably rethink your character's motivations and work on the story from there.

Have a good sense of aesthetic. Let your game have its own style and feel to it. While it is true that new-age graphics doesn't make a game inherently fun, a good sense of aesthetic can help the player get into the storyline, especially in cutscenes.

Keep combat as consistent as possible. While it feels good to have that one lucky critical strike win a tough boss fight for the player, it is equally as frustrating to lose to a random encounter due to a lucky status effect proc. Start by making the combat system constant and tweak it with luck effects from there.

Key quests aren't fun. Do whatever you need to do to keep the player aware of the game's current main objectives and don't make them go on a scavenger hunt for said objective.

Don't use fodder enemies. If a player in the mid stages of the game can easily clear an encounter with a round of AoE spells without even thinking then you are doing something wrong. The idea here is to use "easy, if handled correctly" encounters so as to not upset the balance of power.

Justify encounters. Don't just throw in the old random encounter system and if you do make sure you test the rng for it. Try to find a way that allows for fast dungeon crawling and streamlined level grinding when needed.