Does the user need all the parts to be loaded to use the page effectively ?
If so, then going with the approach of loading parts separately might not be a good experience as users might want to interact with these parts and find that they can only partially interact or not interact at all might ruin the user experience.
However if you can interact with the parts as they are loaded I would recommend going for it as users will be able to perform some actions in the intermediate time. That said, there are some recommended best practises how to handle long load times which you can use for the remaining loading parts
- Keep users informed of how long they have to wait : Users can get fidgety if they are not sure of how long they have to wait. Hence using an indicator to denote how much time is left or how much is loaded can be helpful. To quote this article
On the web, this means you should give your visitors a clear
indication of how long they need to wait. Obviously, an absolute time
would be most convenient. However, a percentage that indicates the
loading process also does the job.
If we see that something is happening, it gives us a positive feeling,
comforts us, and makes us more forgiving – even if the loading takes
longer than expected. Besides, by keeping your visitors in the loop,
you’re playing with your cards on the table and putting them in
charge; It’s now their decision if they want to wait, or get a drink
in the meanwhile.
Here are some examples of sites doing it well
- Inform users about why they are required to wait : A simple way of handling this might telling them about what is loading (like say images or the data is being fetched) with updated notifications to give them a semblance of how much is left .If that data cannot be computed or displayed, try using distractions to keep them occupied while they wait.A good example is HipMunk who uses distractions to keep people entertained while asking them to wait
- Overestimate the wait time while showing it : A common tactic is to overestimate the wait time by a reasonable amount to ensure you can achieve the load before the expected time. To quote this article
Research has shown that beating expectations will lift people’s mood.
Articles and accounts from former Disney employees tend to support the
fact that they will overestimate the times found on those pre-ride
signs. If a guest makes it through early, they end-up with more time
to spend on other rides, or more time to spend money in gift shop
following the ride!
Achieving the expected time seems to be an emotionally neutral event.
However, if the wait is longer than what was promised, a very negative
backlash results. People become impatient and lose faith and trust in
the system. Therefore, the axiom here is avoid over-promising and
This should hopefully give you some pointers about how to keep your users engaged during the weight time and reduce your dropoff rates