TL;DR: Nobody is waiting with baited breath for the redesign of your corporate website, so don't let minor features delay the launch.
For months, you and your team have toiled. You've planned, brainstormed, created, revised, tested, argued, tested, stressed, maybe even cried. The project is close, but there are still a few items on the list. Just a few more features, layout tweaks, and it will be perfect. Crowds will gather at their screens, gasping in amazement at this wondrous new corporate website. Or not. More likely not.
Don't hold your breath waiting for theirs to be taken away.
Why? Because nobody cares about your new website except you. And why don't they care? Because people are busy. Their time is valuable and you've never given them a reason to care before. Let's face it. Your site is not a major Internet destination. Your users are not hitting refresh, desperately waiting for something new to appear (unless you work at Facebook - in which case, forget I said anything).
The old site was stagnant and abandoned. You never published new content or developed new features. There was nothing to care about. Let's be honest, your own employees rarely visited.
But this website's gonna be different right? You've got all these awesome new pages, new features, and a shiny new design! It's almost done. Almost perfect. You've been waiting a few months (maybe even years) to launch this new design and you want it to be impressive when you rip those curtains open.
But here's the thing. Your audience has no idea what new features aren't done yet. If the site is pretty close (meaning it's missing just a few pages of low priority content and/or features)... I'm telling you to put it live anyways.
At this point, anything is an improvement. remember, even 80% is still a "B" on your report card.
What about those other features?
The users don't know about them, remember? Your new site can live without them. I won't tell anyone, it'll be our little secret.
Get this— as you roll them out, you can announce the new features to your users with some well-crafted email and/or social campaigns...Because it was all part of your brilliant marketing strategy from the beginning. It's a reason to toot your own horn, to tell users how a new feature is going to make their lives better. When you spread these roll-out announcements out over the next few weeks you're showing your audience your website is improving, that it's worth revisiting. It's not that old ghost town anymore. Now you're giving people a reason to care.
If you want people's attention and you want them to come back, make yourself useful, regularly.
Build a website that helps them do something. Keep nurturing it. Don't put off a better website with dreams of some "big reveal" moment until tomorrow when you can provide a better experience today.