Hello! I'm glad the plugin is useful to you.
All the things you want are doable, but I want to keep the plugin small and simple.
I have, however, implemented suggestions from Questions 2 and 3 as separate plugin, GRB_NewGamePlus_MultiItems — please check if it does what you want.
Below are answers to your questions related to both versions of the plugin.
About GRB_NewGamePlus.js, the standard version
Question 1: There is no user-friendly way to remove it during playtest, but a simple solution would be to press F12 to open Developer Tools and copy-paste the following into the Console:
delete ConfigManager.newGamePlusEnabled; ConfigManager.save()
Press Enter, and the data will be reset.
(If you can't paste it to Developer Tools' Console, you might need to type “allow pasting” first, or something like that. There should be instructions in the console.)
Questions 2 and 3: Not in the main version of the plugin (GRB_NewGamePlus.js). But see below.
About GRB_NewGamePlus_MultiItems.js, the new more complex version
I’ve just made a more complex version of the plugin, GRB_NewGamePlus_MultiItem.js. It allows to create several “New Game+” items, as well as remove the standard “New Game” menu item.
Note that it’s a freshly-baked untested plugin! If you encounter bugs, please tell me, I’ll fix them.
These two plugins are not compatible. You either use one, or another. Don't install them both.
Question 1: If you use GRB_NewGamePlus_MultiItem.js, you can clear the data by pressing F12 and entering the following code:
ConfigManager.activeNewGamePlusMenuItemIds = []; delete ConfigManager.defaultNewGameDisabled; ConfigManager.save();
Question 2: In this version of the plugin, you can add many menu items in the plugin settings.
For each menu item, you choose a separate ID (like harold_path, theresa_path, etc.; you can't use spaces in IDs).
Then you enable or disable them with the Plugin Command event commads like this (in RPG Maker MV):
newgame+ theresa_path on newgame+ theresa_path off
If you omit the ID, it will enable or disable all New Game+ items:
newgame+ on newgame+ off
In RPG Maker MZ, you do the same, but instead of typing the command, you choose the command from the list. (You'll still need to type the ID.)
Question 3: In GRB_NewGamePlus_MultiItem, I've added the function to hide the default New Game item (in RPG Maker MV):
newgame on newgame off
In RPG Maker MZ, you do the same, but you choose the command from the list (instead of typing it).
(But if all the menu items are disabled, the plugin still shows New Game, to make sure the players are not locked out.)
I hope that helps! If you have any problems and doubts, feel free to reach out.
—Dmy