Here is a forced tank main with 1 tip
Anubarak
if you’re guaranteed to fight, you either cocoon the person who can burn it the fastest or the tank. If they only have one tank and you cocoon the tank, you can jump right into their backline and your whole team can get in there. Otherwise I like to save cocoon to catch people out of position outside of fights so my team has time to collapse for a free kill. (Notparadox gave this one to me 2 years back)
Arthas
Try to keep someone in your E all the time. If nobody is in it you deactivate it to preserve mana. Never open an attack with your D but wait untill you do a normal AA for the reset
Also try to get in front of the target instead of behind the target when someone tries to get away from you
Blaze
Dont light up your oils if you have damage around. You deploy a 50% insta slow, its one of the best CC in the game
Diablo
When you do a wallstun. Instead of pressing E, use your body to bodyblock the target. When he gets pass you, you press E to flip them over
ETC
Its horrible for your rightclickers and abilitie spammers to follow up on a W. Instead of pressing it as soon as you land a stun. Wait a tiny bit before casting it
Garrosh
Unless you are master, dont instalock him. You get a ton of counters. Make sure Johanna gets a ban too. Lock him 3th 4th or 4th
Also unrivaled strenght is extremely underrated
Johanna
You dont pick subdue for the quest reward you pick it for the slow. Try to maximize it in order to put as much CC as possible on a target. You can also trow your shield at one target to get close to another
Malganis
If you pick spreading plague at 7 and bloodrush on 13 you give yourself a nice movespeed every fight. Also dont press E at a long range but do it in melee range
Muradin
Early game your highest priority is to stack your baseline Q. If you go with dwarf block jump at the same spot before engaging in a fight. This will help you get the block before each fight. Dont worry with 4 charges of block and a giant healthpool you will get your charge back if you want to retreat
Stitches
Stitches has a large unit radious and giant healthpool use both to be your teams best friend. Be confident your body more then in your abilitie to be a hooker
Tyrael
Instead of using E for dmg every time. Use it to help your allies engage and escape
Alt+ leftclick to show santification is ready. This will tell others to stay somewhat grouped. So they dont get a suprised santificiation and react bad to it
Varian
Ping the target before you charge. If your going shield wall use the protect to deny dmg to your allies and place your banners on the side not in front of you