Okay this comment is amazing so thanks so much for the advice and I'll try reply to it all here:
With the subtitles I will admit... I was told this by a friend and genuinely forgot... So yeah I shall add them in the full version on launch so thanks so much for the reminder!
With the flask visualisation, yes that's a very good point and a really big oversight on my part so thanks for pointing that out too
With the future plans for the game I plan on introducing a campaign story driven mode that will contain a kind of lore behind the game and the host himself and like solidify it as a game that's worth sinking time into, I also plan on making a system I'm calling "bribes" similar to the buffs where you can bribe certain high ups in the games to gain advantages in the game and rig it in your favour like for example one named "act of god" where if you select the wrong vial the poison will fail and you will be allowed to return "home" (menu) with your cash and more that I come up with.
In terms of the final goal I left it pretty open in the demo to allow players to try keep playing and risk it and their money, using the withdrawal/extraction button on heads as a way of giving them a way out but yes this may have been lost in translation on the cutscene and I apologise for that but past that I didn't give a set win condition so it could be infinite and allow players to aspire to higher and higher runs which will be made more fun by the bribes system I hope. I'll likely call this the "endless" mode in full version so they can still have the opportunity to do that and add more speedrun potential if I so choose to.
Again thank you so much for the compliments and criticism this was really really helpful and just so nice to see people supporting and taking time to help us to improve!