Grammar and vocabulary are going to be two different issues. The words you choose are the building blocks, and you do well at that. Grammar would be the way the bricks fit together, from the level of stonelaying technique up to that of architecture. I know nothing of the relative "usefulness" of Italian and English for certain types of storytelling. I can see how our mongrel combination of bits and pieces from elsewhere has generated layers of richness. The flip side is that its mixed parentage makes English grammar and usage a messy affair. That sentence contained an example - an 'affair' being either 'a certain matter or activity', or it could mean 'an improper or illicit extramarital pairing'. I'll grant that's richness, but it's also tricky. If you can grasp and create puns and double-entendres in another language, I imagine you have a pretty good command of it :-).

Most dictionaries are going to be of limited help with the structure and flow you need to create.

I'm curious - with what you've shared here, did you think it out and even write it out in Italian, then translate it and flesh it out in English? Or did you compose it from the start in English? There's probably value to both ways. Have you pondered whether your feeling that English is richer for this purpose could just stem from your native tongue being "usual and mundane" versus English being to you exotic? To me Italian is quite exotic, thanks to it being wholly incomprehensible, yet musical in sound.

That your command of the language is subtly "off" could maybe be made to work to your advantage. I think of speaker David Ring -- he has Cerebral Palsy and is extraordinarily difficult to understand. His speech is halting and slurred. Yet he is a compelling speaker - one hangs on his every word first because one HAS to, to decode his meaning, but then one is drawn in by what he has to say and how he says it. If it is somehow a part of your story, that the narrator perhaps is operating outside of his own mother tongue, a reader might accept a level of unusual expression, even be drawn in by it. I imagine the critical point there is that your storytelling, the ideas beneath the words, would have to be absolutely gripping. As another consideration, do not shy away from English translations of Italian expressions - those are going to be interesting to English readers just because they're not cliches to our ears.

If you are going to write no matter what, AND you wish to gain skill in using the English language to do so, I imagine just going ahead and writing in English has to be a grand way to learn! If you accept that your first efforts will not chase Tolkien from the bookshelf, yet you have stories to tell that *must* somehow be expressed in English, then Go For It.

It is a maxim worth mulling over, that before one can learn to creatively 'misuse' a skill, one must first master the proper use. I don't buy that 100%, but there's a core of truth there. I take all manner of liberties with English, and I fancy that my meaning is enhanced by the manner in which I write. But having read however many thousand books, hundreds and hundreds of authors, when I type something nonstandard, I'm shooting for a specific effect.

Don't take anything I say as discouragement. There's incredible potential, huge possibility of unique value, in someone carrying out a passion outside his usual domain. A trumpeter is going to have an interesting take on playing the guitar. A weaver could perhaps devise a bridge to astound engineers. So you go right ahead and write !