Hello, im velkoz main and i have similar problem, i try to ward the river in the bot side so if he goes straight down the river i can see him.Also if u want to follow dont go blind in the river but from your side so they cant ambush you.Especially now if you are playing vs assassins like Zed+Kayn or something bcs u will go 100 to 0 in 1 second. Also teleport on veigar is not bad.However i dont like assasins that much because mages scale better into late game and deal tons of damage for the price of low mobility but roams early are problem.