There have been some incredible Eventlabs created by some really talented individuals in FH5. Moving forward, the minus of the next release will be losing these creations that take an incredible amount of hours and a bucket load of patience. Since we now have the fantastic development of Eventlab Island, it may be obvious, but I thought it should be stated anyway, that there needs to be an import feature in future releases so we don’t lose these treasures.
Just my 2 cents that no one asked for 
FH6 may not be till 2025 and even when it’s released FH5 will still be around for years to come. Meaning all these event labs in FH5 if not ported into FH6 will still be around till 2027 if not later.
There should still be insurance that backwards compatibility will remain, EventLab Island is the perfect environment to keep in every Forza Horizon game going forward, similar to how LittleBigPlanet’s two sequels are backwards compatible with all levels from previous, since they contain all features and assets.
I was thinking the same thing. Assuming the next FH will keep up to date with new car models, it would mean that we can play these creations with the latest cars and with no hassle of remaking the maps.
Especially with the effort PG are putting in with new EventLab props and snap functionality, it would be a shame to start from scratch as the platform is very successful. And because it is an island it doesn’t matter where the next game is set.