"Do not load tabs content on startup" option
I always have many tabs opened. And problem happens, when I want to open Opera to visit a site. But as I open Opera, it has to load all tabs' content, which makes it stuck for like 30+ seconds. In not responding state. What I'm suggesting is that, it should open with all tabs, and with their icons and titles. But it must not load their content. Content should only be loaded when that tab is opened and only its own content needs to be loaded. It will save time and RAM too.
Hmm, already available!
It was available as an experiment in earlier Opera-Blink versions and now you can find it in Opera 23. Enable the advanced settings checkbox and under Start-up check "Delay the loading of background tabs".