When you're investing loads of time into your website you sometimes get pretty biased. You may not be able to critisize your own website since you're the one doing all of the work and it would be you critiquing yourself on what you messed up. You would need to see your website in the eyes of your users and also the way Google sees your pages in order to get a good understanding of how Google will overall evaluate your website.
Some of you are saying "If I'm worried about how Google sees my website why should I be concerned what my users think?". You should be worried about what your users see because Google factors their opinions into your rankings. If your website is just optimized for the search engines and not user friendly, then you won't see much love from the search engines.
You can actually get help from your friends and family who are not into website design and optimization to see what they think would need to be fixed. If it's just cosmetic then it's not a huge problem, but if it messed up on their browser or smartphone, then you may have to go back into the code and fix a lot more to please everyone. It's better to get all of this ironed out prior to launching or spending a lot of money on marketing so that you can have quicker success.
A few things to do
Sitemap - One of the first things you should always do is set up your sitemap in order to help index all your pages when the googlebot comes to your page, and it will, to crawl your pages and index them within the Google search results. Sitemaps will list all of the pages you created and let the googlebot easily crawl everything quickly. Not having a sitemap means it could take much longer for Google and your users to find your pages, which isn't a great thing in the long run.
Robots.txt - You'll need to set up a robots.txt file in order to let the search engines know what to look at and what not to index. Anything that you have blocked in your robots.txt file will not be shown within the search engine results. Most website owners will add their contact page, TOS, Privacy, and other basic information pages within their robots.txt file.
Quality Content - Adding loads of quality content will help get your website seen a lot by Google and the other search engines. Just be sure to have optimized and high quality content in order to rank well for specific terms. Ranking for these keywords will send you traffic, but only if you are doing everything right in the eyes of the search engines lol. If your website isn't seen well when google or the other search engines spider it, you won't get ranked well even with great content. By adding fresh quality content you're increasing the chances of being loved by Google.
You'll need to step back and take a real look at your website. If your pages are a little off and you can't figure out why, don't be afraid to ask for some help from a friend or family member to see what they think. You need to be dilligent when it comes to keep your website fresh with quality content and making sure that everything is up to the standards of Google and the other search engines.