I've been making games and writing about them(on and off) for thirty something years now. I don't claim I know how to make a great game, but here's a list of general design and tool specific tips(in no particular order) to help you make the best out of your tiny RPG's.
1. Game length is not an indication of quality.
"This game is boring AF, but at least it's long, " said no one ever. Not only that, but having a long-ish game without dedicated save function just sucks. The bottom line- don't maximize for length.
2. Don't try to do too much
One good quest per game is enough, but if you want to do more(and I know you do) plan for at least 3 screens for a main quest and at least 2 for each side quest to create a feeling of space and time. Ideally 5 and 3 respectively. So basically one main quest and up to 3 side quests on the default 3x3 map, since you can do some quest area overlapping. More than that and there will be way too much backtracking and it will feel like everything happens in one place.
3. Tool labels are just a suggestion
Think of it like this instead: terrain tiles are for elements you want repeated in one screen(both passable and solid). NPCs are for unique solid elements, that may or may not be repeated on other screens and/or may need to disappear.
4. Just because you can do something, doesn't mean you should.
Think if it serves your design or you're putting it in, just because the functionality exists.
5. NPCs are your quest items.
Reskin them, set a variable for later use, write a text message you picked the item, set them to disappear. Voila, you picked a quest item.
6. Reskinned NPCs can be used as extra unlockable doors, information system or temporary roadblock.
Sure we have default elements that do that, but those are limited to 1 per screen. NPCs are not.
7. You can reskin the XP scroll...
to look like your quest item so you get XP when you find it.
8. Don't go overboard with long dialogues.
If your text is longer than 5 dialogue screens(per NPC), it's way too long. Use environmental storytelling instead to tell your story- find items with telling descriptions, notes or diaries that tell the story etc.
9. Create memorable areas on the map through environmental change and unique features.
Animated sprites or reskinned NPCs are great for that. Make every room unique visually- have a clearly different layout and gameplay- the room with the lever, the room with the chest in the middle etc.
10. Your dialogue choices does not have to be a "yes or no" ones.
Just link different answers to your ✗ and ✓ options, similar to how consoles tie answers to buttons.
11. Optimize your canvas space.
Boundary wall placement depends on the entry point and your initial moving direction. Every time you first enter a room, you must see which directions are available straight on. All the walls are defined in the same room, absent walls that were already defined in the previous one or by the map outside boundary.
To make things easy for the players use "path" tiles to show possible exits.
12. Use this adapted version of the classic dungeon checklist to make sure you produced a viable RPG.
Do you have:
- something to kill (normal enemies)
- something to be killed by (boss enemy, requires leveling and loot to beat)
- something to find (loot, secrets or story segments)
- something to steal (loot you can get without fighting, just timing the enemies)
- something to tinker with (puzzles, levers and traps)
- something to talk to (a character, a sign to read or just a baloon text detailing the environment)
- different paths (or different ways to move around an obstacle or fulfill a quest)
If yes, your tiny game is just fine.
13. For narrative games don't go crazy with the characters.
A 3x3 world with 7-9 characters to interact with is enough. Yes, we have more NPC's available. No, you don't need to use them all.
14. You have enough sprites(and game elements in general) for everything.
For each environment/location you NEED just one moving sprite(to make it feel alive), one wall sprite(trees are walls) to create boundaries, one path sprite and one normal floor sprite, two normal location appropriate enemies(just one for side quests) and one boss enemy(optional for side quests). The rest are "detailing sprites" that create uniqueness, beauty and flavor in each location. Use them accordingly.
15. Music is a great boon to your game(when done right)
But make sure your music theme is good and is long enough so it doesn't get repeatable. Even a great melody gets boring fast if it's 30 seconds on a loop. If you're stuck between choosing no music or bad music, go for no music. At least that way players can listen to whatever they want while they play.
That's it. My 15 tips on making a good RPG in TRS. Ultimately though the most important thing is you don't forget to have fun and experiment :)