I got into GW games around 1995. The game store I co-owned expanded to include Warhammer with all the surplus Magic:TG cash we had, and all of the owners started armies to learn the game. I selected Undead, and this was in the days previous to the splitting of Undead into Vampire Counts and Tomb Kings. It doesn't seem that long ago, but I've been playing for almost 14 years.
Anyway, Magic:TG was a cash cow in those days, so we had even more surplus cash - and we decided to carry 40K as well. Once again we all selected armies and though I was torn between Orks and Dark Angels, I opted for the DA's successor chapter - Angels of Absolution.
Back in those days I remember playing Warhammer against a kid named Mike Mattlock. He played Empire and I don't think he ever won a game. He tried so hard. On at least one occasion I got a first turn win on him. We spent 45 minutes setting up. I got the first turn and I rolled for all 3 of my Screaming Skull Catapults and they all hit their mark. Units panicked in droves and this caused chain panic in the other units. I cleared almost an entire army off the board with 3 well guess shots, and Matt failing countless leadership tests. It was frustrating for both of us because we put so much into getting the game set up, and it was over inside of 10 minutes after deployment.
My earliest experiences with 40K were no different. A Virus Outbreak strategy card could clear a Guard Army before the game began. Was it Karandaras with Combat Drugs who got the first turn charge almost guaranteed and most likely tear the heart out of your army? (Note: armies were much smaller then.) Entire Wolfguard units could be equipped with Assault Cannons and Cyclone Missile Launchers. Vortex Grenades. Vortex Grenades! The list of insanely broken elements to the game goes on and on.
We eventually created additional limitations for both games like "no magic items over 50 points" and removing Virus Outbreak from the deck or Strategy Cards and denying Vortex Grenades as an option. That, and I outright refused to play the 12 year olds in my store with their Space Wolf Wolfguard.
I eventually went to work for GW when they opened a store in Buffalo, NY and I left the store I co-owner for a job with a paycheck. Before I was promoted to manager, I was rewarded for my commitment to the store by being sent to both the US and Canadian staff tournaments.
At the Canadian staff tournament, a guy named Sean Murphey deployed his enire army in 1 building. His opponent elected to shoot at the building instead of at any of his units. He blew up that building and Sean Murphy's army perished in its entirety on turn 1! They created something that day called the Murphy's Luck Award and whoever came in last at a staff tournament got a new boxed army of a different force than what they played with in the hope that they could do better with it.
People on the internet are always screaming bloody murder whenever GW does anything - its always the "wrong thing". The latest whining is about the impending 5th Edition that is "ruining 40K" before its even been released. Its also being endlessly asserted on the internet these days that GW have thrown game balance out the window.
Every edition of both games has gotten better. I haven't seen an army tabled in either game on the 1st turn since the late mid 90's. 5th Edition Fantasy and 3rd Edition 40K both made changes that prevented these sorts of things from happening.
Yes, your army is going to play differently.
Yes, you're likely going to have to convert or buy new models to adjust to the changes.
Yes, you're going to have to spend the next 5 years adjusting to the new ruleset just to have them tweak it again.
Embrace these things. Change is good. The game would get stale otherwise.
And as for game balance - there are too many variables with that many races. Perfectly balanced army lists is a myth. Its a concept that does not exist and it never will. Maybe if they cut both games down to 4 races each it would be possible, but then we'd lose all the character and variety that make the game so engaging.
Finally, if you can't adapt - get out! Seriously. I'm astounded how many GW haters still post on forums and comment on blogs. If you don't like the models, you don't like the prices, and you don't like the rules, then why are you here? Do all of us that are actually excited about the hobby a favor and take your crybaby bullshit elsewhere and rain on somebody else's parade. Personally I suggest politics where maybe you can focus all of that negative energy into something positive.
This is not a plea, its a demand. Sell your models and get out!