Writers are insecure bods on the whole. And the following scenario may be familiar to you:

Oh dear, you say, it's time to start my next project. Well, what I really want to write is a tender romance, because what I get most into is intimate character interaction - but romance is a pretty formulaic plot. I'm not very good at plot. Proper books have plot. I need to improve at plot. I think I'd better keep the romance as a subplot add a twisty detective story to make sure I'm doing everything a book needs to do.

This is technically known as 'working against yourself'.

Of course it's good to develop in areas where you aren't so strong. And there's nothing like practice for developing. When I did a Creative Writing MA, I felt I was weak on dialogue, so picked a minor that involved writing a play, to force myself to do something that involved a lot of dialogue. But - here's the thing - that was by way of an exercise. If you're outlining a major project, that's not an exercise. You learn a lot writing a book, but mostly you learn how to write that particular book. It doesn't teach you how to write the next one. (I really wish it did, but alas, it doesn't seem to.) Feeling a bit worried that you might not be that great at something is no excuse not to try and make it work - but what you shouldn't do, if you want to write a book and sell it, is map out a project based on supressing the things you have a personal yen for.

The logic goes something like this: I don't find it very difficult to write, say, action scenes. That must mean that action scenes aren't very difficult to write. So action scenes aren't very impressive; I need to write a book that depends on other kinds of scene.

This is your logic bone trying to kill you. Yes, you shouldn't write a book that's nothing but one long action scene, because that would be boring, but you might consider that possibly you don't find action scenes difficult because you're good at them. And considering that, maybe you should write an action thriller, rather than an historical novel about the first love of a pacifist Quaker maiden. Neither kind of book is inherently better, but a good action thriller is better than a bad Quaker romance.

Which is to say, you need to find the plots that give you scope to play around with your preferences. I wasn't particularly interested in werewolves per se when I wrote Bareback, but I was interested in outsiderdom and body dysmorphia; werewolves gave me the scope to do that. What you really need is not a plot that hides your personal preferences, because, while the personal is intimate and can hence easily feel embarassing, there's actually nothing shameful at all about prefering high melodrama, low-key realism, complicated plots, a well-done formula, reflective melancholy or joyous feelgood. Whatever your preference, I can pretty much guarantee that there will be thousands of people who share it; it only feels embarrassing because it's yours.

What you need instead is to find a plot that gives you an excuse to write about the things you like. The right preference in the wrong book probably will create a mess, and that is a bit embarrassing, but the right preference in the right book creates a novel that works perfectly.

If you prefer writing green to yellow, set your story in a forest; if you prefer writing yellow to green, set your story in a desert.