If you really do have a legitimate 1500 msec process occurring on the home page, try to flush as much of the HTML to the browser before you start the heavy lifting. Ideally, you could have the entire HTML shell delivered immediately, and the content elements slotted in at the very end (using DOM manipulation).
If you can put all the content inside a <script/> tag at the very end of the HTML, it will at least give the browser a chance to find and download all the page's resources (css, Jquery, logo image, etc etc).
Make sure that http cacheability is good (send proper http headers, e-tag and expires; serve assets from cookie-less sub-domain). But if the page renders in 1.5 secs, I would try to address that also. That's highly specific to the application and its technical platform, so I couldn't really say how to approach that - But break out a profiler and go for the big chunks for a start.
Impossible to say without looking at the profiled request. One thing I can say it's I would look at any page-level / HTTP caching until page generation is at least under 300ms for the most common requests.
If you can put all the content inside a <script/> tag at the very end of the HTML, it will at least give the browser a chance to find and download all the page's resources (css, Jquery, logo image, etc etc).
e.g.