How is tenure-track start-up in Europe?
I think the issue is that the concept of "tenure-track" doesn't really exist in many European countries—at least not as it's interpreted in the US. Consequently, start-up packages can be difficult to compare.

When I started my present position, I got a very small package, if you reckoned it in terms of what's needed to buy equipment and pay for travel. On the other hand, I was guaranteed two full-time scientific positions for the lifetime of my appointment. (These positions could be used for either PhD students or postdocs.) Reckoned in that sense, however, the package is quite generous (close to $1 million).

In other nearby countries (Netherlands, for instance), the support is not nearly so strong: typically just one student supported by the university, and relatively limited budgets.