You're only pushing him closer to the black and white overbearing or useless scenarios.
Vlad has general usability and impact issues. Not issues staying alive.
When he does stay alive, his impact is null against anyone that's smart enough to invest in a single MR item, even with Void Staff.
Increasing his ult's healing does not address any of his issues, especially since most of his issues come from teamfighting.
His E needs to have more guaranteed impact when he manages to land it, considering all of the factors going against him. Bonus MR penetration, like GP's barrel, when he fully charges E would be a great place to look.
Another option is increasing his general usability by tweaking his huge cast animation times and delays, specifically tail end of W and his Q/Q healing particle. He cannot function in the situations he should excel in (low HP, close fights) because its nearly a full second after you try to cast Q that you get your healing. Around 2 seconds you're waiting after W ends before you get your heal if you cast Q immediately when it lets you.
**Please consider fixing his unintended issues first, then look to buff if he's still weak.**