get a scv to follow him to keep the pressure on him and you can see where he is going to build his pylon, make sure you scout around ur base meaning your shadow areas etc. worst come to worst if he manage to cannon cheese you, gather a bunch of marauders and snipe the pylon if possible

reapers works pretty well against double gate zealot rush and you can harrass his probes as well

get more rax... at least 3 since you know its a toss dee mass marauders works pretty well against them


against zerg you can consider to build some turrets instead? if he's getting muta i think stim marines works pretty well.. not so sure about late game. i'm not really a terran player