For me there has to be a few things in an ico before I invest. Only that I've been burned countless times in the past.

1. A proven track record of setting targets and meeting them
2. Honesty and transparency between investors & the core team. That way if there is a delay in the project then people that laid their money on the line are the first to know.
3. A credible track history in the market they wish to incept - if not, then a bunch of transferable skills, and a bright eyes and bushy tailed approach at what they want to achieve.
4. Realistic goals
5. No price forecasting. i.e. invest now and watch your profits go $$$$$$$$$$$

And a few others, but I think those are the main ones for me.

We invest in an idea; so broken English and a rubbishy website isn't enough to put me off -- they might have a fantastic idea and a real credible team to get stuck in to whatever it is they are planning! Language and Design skills/team would probably come after investments start rolling in.