Direct stock purchase plans - your thoughts?

It wouldn't make your taxes 'worse' really, it's just more to keep track of, which means more work for you.

Say you want 6 different individual company stocks. After the initial purchases, if you want to invest a little more each month, you then go to 6 different places if you want to keep even investments in each company.

Then come tax time, you have to account for 6 individual stocks. If you sell one early or do something different with one of them, you have to account for that individually, and make sure you have it all tracked ahead of time.

It's not 'hard' by any means, it just takes more time to deal with it.

But honestly if you're looking for diversification, individual stocks are far from it. Yes, it's definitely better to go for multiple stocks rather than just one, but an index fund is going to give you much broader diversification with much less headache (and likely lower costs as well). Vanguard charges me the .10% or whatever it is (depending on the fund you choose) on my earnings, but it doesn't cost anything to buy into it.

What makes you think that you know how to pick an individual company that will do well in the coming years?

This is a question where most people think, "Oh, well I know a lot about cars, and Ford makes good cars." This is not a reason to buy a particular company's stock. Yes, Ford might make good cars, but they might not be selling well. Or the minimum wage in the US might go up, and therefore Ford's costs go up, and they end up losing money. Or they might take a few years to start outsourcing, and lose money for a few years while the outsourcing happens. Or they might get found guilty of some legal issue (like Amazon's ebook price-fixing issues recently, or Samsung/Apple's patent wars, etc.).

Yes, giant 'blue-chip' companies will likely make you money in the long run, but unless you're buying individual stocks in multiple sectors and multiple company sizes (small/medium/large companies), you're not diversifying as well as you could be.