While some gains can be had from further optimization I doubt we can significantly improve the loading times. In the case you have grass enabled and texture quality set to Ultra there's a lot of stuff to load especially in the case of newer tracks that have a lot of foliage variation and use multiple terrain blend maps. If you're running low on memory will cause a further slowdown to loading due to swapping (having your page files on SSDs will help somewhat in that case).We'll check out whether it would be feasible to add a 60 second safe margin before timing out.
While I hesitate to necromance a thread, a friend of mine was having this very same problem, unlike the rest of the players. He turned down the grass and it didn't help matters notably. We'd all be loaded and see that he'd have a steadily-increasing ping, sometimes as high as 22 seconds, and would take over a minute to load up. If I started the race as soon as I was loaded, there'd be no way he could make it on time.I found we could greatly improve his loading time by removing all the bots before switching tracks. We tested it several times, both with a full complement of bots, and with an empty (besides us) lobby, and his loading times were always improved the fewer bots there were. I also experienced an improvement in loading time, but nowhere near as extreme as his--from upwards of 60 seconds to just 5.So, at least in his case, the extra cars caused a problem. I don't know if it was specifically bots or players in general as I didn't have enough players to meaningfully experiment, and didn't want to inconvenience them further.
Would friend be using a wireless connection? Zeb saw this happen with his laptop and a wireless connection one Saturday night.