Yeah, he's pretty derpy right now.
If you random him though, there are things you can do to make your life a lot easier. For instance, you don't really want to gank people 1v1 when you are just starting to gank. This is where Bloodseeker differs from people like Nightstalker. Ideally, what you want to do is just appear in lanes where you have allies to assist, because then they really can't escape.
And I personally found that he really, REALLY needs these early ganks too. Because what happens is that if you don't get a good level advantage at about 15 minutes in, then you simply cannot kill anyone fast enough before they get away.
Another thing that I found useful is that Bloodseeker isn't really a carry and shouldn't be farming too much. He should spend oodles of time ganking and being incredibly annoying. Because of this, I only ever keep his heal at level 1, while I max his speed increase second. I do this simply because I find the ability to zoom in on targets half the map away and have a permanent movement speed buff to be more useful than the heal. After all, my whole intention is to appear when the enemy has no chance to win. I don't really want to get into fights where the enemy thinks he can beat me. Gotta go fast!
So basically what I do is go mid, farm a bit till 6. Check lanes. Gank nonstop. Apply bloodrage on enemy supports, or on myself if there's no point silencing the enemy for EIGHT SECONDS. Get a few kills. Snowball out of control. If no kills, lose.
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But yeah, because he's so dependant on those early ganks, it's really easy to lose with him.