First off, as you are talking of the expanded format yourself, you should be aknowledging that the expensive cards that will help you in those six months to come of Primal Clash-on metagame (for the Standard format) will stay useful after the rotation, since Expanded leagues exist. This means that your cards never really lose all of their value and playability, you can still get use out of them. I tried Mega Evolution decks on PTCGonline in the Standard format without Shaymin-EX (since it is not part of my digital collection) but almost everytime, with the exceptions being when I drew really well, they have proven to lack a good part of the consistency and speed they would have were at least two (or maybe even one) of them to have been in the list. As a side note, if you run Shaymin-EX, you look at an Ultra Ball in an entirely different way. Dead drawing becomes harded. If you are scared of them getting Lysandre-Knocked Out, or of running out of Bench space, then you really should just consider using the Despair Ray version of Mega Gardevoir as a one-of, in order to get rid of them. Then, using Super Rod, you can shuffle them into your deck for an eventual second use. I am not saying you should/must have four in you deck in any way. (The Brilliant Arrow deck works best with two or three in my experience). What I am saying is that one Shaymin-EX would be a great way to speed up your deck and make it more consistent, and you can use it in basically any deck you would like to build, and even in Expanded after it rotates. If you really do not want to spend this much money on one card, then I suggest you try some other draw supporting Pokémon like Octillery, especially given the high amount of turns Mega Gardevoir might take to get set up.
Secondly, I am a normal person; I do think Shaymin-EX's price/apparent value seems strange for one card, but with the exception of a few decks, it is very hard to do well in competitive play without it. Its price is justified by its competitive value and demand, the reason I consider it a good investment is that it will improve so many of your deck, and as a result, you should be more successful in tournaments and earn more prizes, and possibly even rank well at league events and gain CP towards the big tournaments. If you are wanting to play in competitive without spending oddly high amounts on single cards, I suggest you wait until the BREAKthrough-on format (the cutting point being my speculation), where a fairly budget Mega Gardevoir deck, as I've previously explained, could do very well, given the speed of and the cards that seemingly will not be in that format. If you are looking to play casually, I think you can do well without Shaymin-EX, but that this card will still advantage you significantly.
First off, I'm not a competitive person ... in general.
That aside, in any other tcg, if you know for a fact that a card will be banned that card loses all value. People are throwing them at each other, hoping someone will take it from them before that drastic ban comes into place. It won't just be pushed to expanded it'll eventually be pushed out off that as well ... again how can you as a 'normal' person say one card is worth 50 bucks (that's a month worth of food/drinks for me btw ... A MONTH) knowing it'll become unplayable? It's good for a year, one big tournament and then you can throw it in the trash again (figure of speaking of course).
For anyone with a brain that doesn't just go around splashing money not realizing what they're actually throwing away, this game is totally broken. At my locals (or anywhere I've been where people play(ed) pokemon) existing players disappear with each rotation. New players come as children, who are honestly to young to play because they can't read/understand english and can barely make decks. Those that are a bit older just take decks from online and hope their mommy and daddy pays for it (surprisingly a lot of parents are stupid enough to do so as well). But a lot of those children after hearing the cards they have will become illegal to play or are already out of standard, sometimes out of expanded, they get close to bursting into tears. Same as my little brother, you can't understand how disappointed he was hearing that what he's currently playing is actually not legal in standard. Luckily on that part he's a bit like me and instead of being sad/mad, he was just honestly disappointed by it. Even people who come back to the game with cards they had years ago, what do you think they do after hearing they aren't allowed to play the cards they currently own? They're not staying, they turn around and walk away.
Existing players are turning into teachers, teaching new players (children) how to play, while they barely play themselves and resort to just collecting because they slowly start to realize how terrible this system is.
There are a number of players where I go now, who have resorted to never buying boosters or single cards. They play the sneak preview or early release tournaments and hope they get something there good enough to trade to get themselves the cards they need/want. Once in a while when there's a tin box or special box with cards they want (again to collect) they'll buy one of those. For example the mythical collections from a while back with the full art legendaries.
Honestly, on wednesdays or saturdays I sometimes go to play pokemon at my locals and there's little playing happening. It's basically just a bunch of us guys helping children out and having a chat.
If it wasn't for 2 little brothers asking me to teach them, I wouldn't even be playing it. I'm pretty sure if I never got to play this gardevoir deck from someone at my locals, I would still be playing against my brothers with my old dusknoir deck which I've put soooo much effort into making and is completely unplayable/illegal to play now.
This is why I hate competitive players btw, I've yet to come across a competitive player who actually put a lot of effort into his/her deck. Playing it for years to see where its strength and weaknesses lie and trying to push it so hard that it can keep on running alongside newer, stronger more improved decks.
No, they just jump from deck to deck splashing around money until they get into trouble, being forced to sell everything and stop playing (that's for the adults who don't live with the parents anymore). Decks that are running on the front side of the meta ... these are the players that ruin games for those that aren't like them. These are the players that make tournaments super boring because it starts to lack diversity. One of the main reasons I never went to big tournaments for vanguard.
As a newbie you get diversity in the start of these tournaments until you start to win, that's when you get to see the same thing over and over and over again.
how long do you want me to make this? XD
PS: don't take anything personally, I'm talking in general here. Not aiming anything really towards you.