I can't bring myself to buy those passes, one because I resent the cost (more than the cost of tickets themselves) and two because I don't really like the idea of my kids thinking you can be billy bigshot waltzing past the queues showing how important you are compared to the plebs.
That said there have been times where I've been stood in queues for over an hour with an antsy child wondering why we've bothered. Summer holidays it will be very busy.
Reserve and Ride regular is maybe worth it I guess, I'm not too fussed about long wait times if we don't have to physically wait in line, just do something else in the meantime.
The Ultimate thing for £90pp though, I mean for a family of four that's £360 on top of your entry tickets, so perhaps £500 for a day a legoland just seems exorbitant to me.
Rainy days are actually a really good time to go to Legoland/Chessington because by the early/mid afternoon a lot of families decide to pack it in and you can walk straight onto some rides and much smaller queues on the bigger rides.
One thing to keep an eye out for is reduced capacity on rides which will increase queue times, e.g. the fire engines sometimes they only have 1 side open (so half the throughput), similarly with Squid Surfer they had some disabled once. The good news I assume with lockdown ending there will less restrictions on social distancing meaning less wasted space on rides.
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