[FS.Kezz]

I haven't watched your replays, but I will give some general advice:

1: Don't build blue-flame hellions into a bio composition. The resources you invest into those could provide you a LOT more marines and marauders. For maximum effectiveness, stick with pure marine/marauder/medivac for that first timing attack (should include stim, combat shields and the +1 attack upgrade).

2: If you're going for a timing attack, it will only be as strong as your macro has been for the time leading up to it. Hit up the FilterStarCraft series (youtube.com/filtersc) for perfect help on this. There is nothing wrong with starting at the Bronze level videos even though you are in Gold, because it will give you the fundamental mechanics.

3: In terms of micro when engaging a Protoss, there are 2 quite easy things you can do that will help you a lot in most engagements. The first is to pre-arrange your bio into a concave. This mitigates a LOT of the Protoss AoE damage (which is where their strength lies). Keep an eye on where the enemy army is (don't be afraid to scan!) and make sure that if his army comes anywhere near yours, your army is already arranged into a concave. The second one is to let your Marauders do the tanking! Once you stim and give the first attack command to your whole army, ctrl+click on 1 marine (to select all marines) and micro only your marines around.

The Protoss will be attack moving his Zealot/Stalker/Colossus army and your Marauders will soak up SO MUCH DAMAGE, including storms, Colossus lasers, and Charged Zealot onslaughts. Ensure a decent number of Marauders in your composition to do this effectively (~3 for every 10 marines). Meanwhile, your marines deal out their damage, first focusing down the big expensive units (Colossi, Immortals, Archons, High Templar, Sentries), then killing the remaining Stalkers and Zealots. Keep in mind that all of this happens very quickly, and you can't expect to get it perfect the first time, or every time just yet. Repetition will make these engagements second nature after many many games and you will find yourself loving TvP once again.