Without having seen the paper, I would suggest that changing it from a full paper to a research note will probably not help. Hopefully the editors of the journals who have desk-rejected your paper will have provided you with a brief explanation for their reasons. The best thing you can do is think about those comments carefully and improve the study or the presentation of the study - whichever the reason for rejection may be. I would generally not recommend submitting papers to journals that do not have a reputation of being of high quality. It could actually weaken your CV, rather than strengthen it. The best recommendation I can give you on the long term is to read many journal articles published in the journals you would like to publish in. You will soon find out what the key features are of the published papers. This knowledge will then inform your future studies and increase your chances of getting your work published in top journals.
On another note: as a journal editor it breaks my heart if I have to reject papers, so I wrote a short Viewpoint article explaining the main (and easy to avoid) mistakes authors make that lead to desk-rejection. This is primarily for quantitative survey studies: https://doi.org/10.1016/j.annals.2020.102981
We also had a webinar dedicated to this topic that you may for of interest: https://www.journals.elsevier.com/annals-of-tourism-research/webinars/webinar-series-bite-sized
I wish you the very best for your next submission.
Best wishes
Sara