Solo kills are worth 300g, team kills are worth 450g
Why? It gives me no incentive to kill my lane opponent until my jungle arrives for that free extra 150g. Killing my lane opponent without my jungler merely racks up my bounty by 100g (for a potential 550g, 250g more than the kill I just got).
What's worse is if you go for that potential 300g kill you may potential fall into a camping jungle gank that nets the opponent 450g for what would have been 300g for you. There's just no incentive to go for kills.
Same goes for first blood. FB is only worth 400g solo and 600g with 1 or more assists.
The reward for teamplay should be an easier take down, not a more rewarding take down.
You ask why top lane feels bad? This is why.