What is the best counter to mass marauder while using a standard build order? I have tried charge zealots but the just get kited to death. High Templar with storm do not do enough damage. Colossus are also easily sniped. Void Rays are good but switching to air is sometimes not an option when you have already built production structures. Maybe zealots and archons? Does anyone have a successful counter to this?
I'm not sure how each one of your examples are not working as they are viable with a little bit of tweaking.
I notice that you don't have any sentries listed there and they do help in your fights, guardian shield reduces the damage from marauders and they also provide your best ability to deal with them, forcefields.
Combining all of the above will make mass marauder completely useless against you. A protoss death ball with enough sentries, zealots, stalkers, an immortal or two, and colossi can split their army in half, lets your chargelots hit the ones inside the forcefield (yes they'll get hit by the ones split off), lets your stalkers fight a smaller force, lets your immortals obliterate the marauder numbers, and lets your colossi rip through the close ones before attacking the farther one will destroy their army. It's a bit micro intensive, but probably the best way of handling them overall.
Zealots + Sentires, is THE BEST option, the only obstacle is learning how to places FFs.
Here is the guide for that Using Force Fields Effectively
You're asking the wrong questions, consider these:
How do I notice that my opponent is going for mass marauders?
Scouting is key. The point of a fast-paced strategy game like StarCraft II is decision making in time, in order to win you need to make the right decisions and execute them before your opponent does. So, it is important that you gather information about your opponent; earlier is better, but not too early.
Read this post by our fellow tzenes, it contains lots of options for scouting and where to pay attention.
In order for your opponent to go mass marauders; he would be going for multiple Barracks all supplied with a Tech Lab, and you would notice that he mainly has Marauder units rather than Marines. If you want to take it to the next level, you could also pay notice at what upgrades he got from the Tech Lab. An early Concussive Shells could be a good warning sign...
What are good accessible units that easily allow me to take down the mass marauders?
Let me first tell you which units are not right, and why; some of which you listed first:
Now, if we take the tech tree and start scratching the wrong options, it gets interesting:
But they also have their downsides:
Can we live with the drawbacks?
Stalkers can be used in a defensive setting, this way it doesn't matter if they are slowed down. Immortals don't really have a problem because the Stalkers serve as a good meat shield for them.
So, yes, the advantages outweigh the drawbacks.
What happens after I build up my first defensive army?
You've probably guessed it, you are going to get outnumbered or your opponent changes tech. But, as I said in the beginning, scouting is key so you should have made a single observer to figure out if he is teching to something else at home.
Let's check both options:
The ideal composition against mass marauder (potentially with viking support) is Zealot (with charge) and Archon. Stalkers are useless and Immortals are good in theory, but they are easily target fired and difficult to mass produce. Templar are also good in theory, but with stim, storm dodging is very easy and templar are easily picked off and/or feedback'd.