What type of level should I build?

Rather than vote I would like to make a recommendation. Given that you're a new creator it will be difficult for you to create something on demand to rival the hundreds of well crafted levels on this forum. I would thus suggest you focus on the type of level you feel most comfortable with and have the most passion for.

In other words, give us your best rather than something mediocre that tries to appease a handful of voters.

That being said, the question of favourite genres has come up frequently over the past tens of months and logic levels seem to out-favour others, particularly skill-based ones. The challenge to find the one solution to a unique and adventurous puzzle is much more popular than a level that can seem random or dependant on the player's hardware platform. Remember that we have people of all ages here and this is not Roblox.

 

@delator77, tu inglés es mejor que mi español.