This next match-3 project likely will be fantasy themed because I already have a whole bunch of character art. Painting backgrounds and icons is my weakness, but I can buy some through the Unity asset store. I spotted some great special effect packages too.
Match 3 always will be popular, and is already "fun" from the beginning. The design challenge is going to be crafting all the interesting features that extend out the game, while offering sufficient strategic elements to prevent the experience from getting dull and monotonous.
I believe as long as there is gradual and continuous progression through occasional unlocking of interesting features, then the game will surely be a success. A game like Zombie Guard is not necessarily fun because of say, the weapons, but rather, the unlocking and upgrading of the weapons. This has been a general design focus in all my games. Typically I strive to create the core of the game, and then insert a lot of content with data driven systems for weapons, skills, items, and AI character types.
Since this will be a turn-based match-3 game, I can write some simple AI to play-test the game for me. I have a spare phone to have AI play stable builds 24/7.
From the very beginning I will be setting the game up for easy localization into other languages. If done correctly, all I would have to do is gather translations privately from various people who have already contacted me. Ideally, it will be easy to update and append translated text through external data files.
So, that is that.