Re: fly box
I don't know if these particular tin boxes have the required thickness to accommodate streamers but I would venture a guess there is a box out there that does
Poor quality materials are destined to discourage beginner tiers and cause greater expense when the time comes to replace them.
YOUR way is not the ONLY way when tying flies!
Fly tyers can be masters of making things complicated!
You're only limited by lack of imagination. Be creative, experiment.