Don't get held up decisions like this. Just pick one and move on. Moving forwards is much more important than getting this 'right'. Besides, if your startup fails because of which TLD you chose then something seriously weird has happened.
Take .io
I know it's not your fault but .ro can lead to suspicions and disbelief about your capacity. :/
And you don't want that for your incoming startup ^^
The recent Paul Graham essay (and discussion) is worthwhile reading on the topic of naming:
https://news.ycombinator.com/item?id=10030863