Hiya [USER=39789]@4275purplerainbow[/USER]
Just wanted to chime in and offer some support. Although I'm sure [USER=36777]@Andrei Radu[/USER] [USER=36740]@Amma Usman[/USER] and [USER=2672]@Jessica Booker[/USER] would also have more to add here. I completely sympathise with your point about the challenges faced by non-law students. Non-law graduates often struggle in the application process because they may have less exposure to legal practice areas and may find it harder to demonstrate a clear understanding of a firm’s work. In recent cycles, I've read posts by many non-law students on TCLA who've mentioned how difficult they find it to articulate why they're interested in commercial law (beyond the general idea that it involves businesses and transactions). That said, it's important to note that the cycle isn't over and it's completely possible for you to secure a TC through a direct training contract application.
In my own case, I came to commercial law from a completely different background. But I think there are several ways you can strengthen your profile before reapplying next year. I found attending insight and open days extremely helpful in allowing me to start gaining a sense of different firms and their specialities, as well as where they sat in the broader market.
I'd also recommend gaining practical experience in a legal setting, though this isn’t strictly necessary. For me, this was largely done by working in legal clinics during my studies and on pro bono projects alongside lawyers from large commercial firms. But you can also start applying for paralegal roles or even business development and compliance roles. I've generally found that many places are open to hiring graduates from diverse backgrounds for these kinds of roles.
One area that I think many, many applicants struggle with is commercial awareness. I'm really pleased that more people are recognising how challenging this can be for applicants. I'd highly recommend reading through ZipLaw, LittleLaw and also reviewing any TCLA threads on commercial awareness. Most law students often find it difficult to really draw out the financial, economic, and political implications of certain stories and trends. Given that your background is in econ, I think it's worthwhile thinking more about the legal aspects of the stories/trends that you're interested in. This could help ensure that your commercial awareness is more targeted to the legal profession and focussed on what lawyers do.
These are just some ideas that I wanted to send across, but I really think you can get that training contract. Keep at it and let us know if you have any questions about firms you can apply to for a direct training contract during this cycle 
