If we have this huge pool of miners out there, then why are transaction speeds so slow? Surely the more miners, the faster it should go. If not, there is something fundamentally wrong with the algorithm.
Mining has nothing to do with the speed of the transaction. Please study more about Bitcoins before posting something that will blow in your face. If you want speed then use Steem with 3 second transaction but it is worth only 1.35 dollars as of writing. Ethereum with 15 second transaction but is worth less than 500 dollars as of writing. What about Bitcoin? It is worth 6,000 dollars as of writing. You complain that it is slow. Try to learn how to sweep private keys and you will feel the speed.