Haven’t tried the Valhalla Delay yet but absolutely love their Freq Echo, which has the added bonus of being free. I also really like the Dub Machines set (https://www.surrealmachines.com/product/dub-machines-vstau/) which has one Space Echo emulation and another device which is halfway between delay and reverb, capable of some really beautiful stuff.
On the hardware side, I’ve just got an RE20 after lusting after it for years, still getting to grips with it (and trying to find ways to use it which don’t fall into generic Space Echo territory) but very impressed so far. I’ve had a Memory Boy for a while, which is great for your typical BBD sounds, and a Behringer Echo Machine which is surprisingly good (particularly the ping-pong delay mode) for something which cost me about 20 quid. Agree on the tape delay effect on the SP-303 as well, extremely grungey but sounds lovely.
I’ve also got a prototype tap tempo Eurorack delay made by a Scottish friend which is wild, noisy and very, very fun. Don’t think it ever made it to production, which is a shame, but it does have the absolutely flawless name of Taps Aff.