For reverb at least, you could try some Lexicon. The MPX1 can be had for around 200-250 GBP - it uses one dedicated Lexichip for reverb, and another DSP for the rest. It's programmable without too much agony, and sounds good.
I have a pair of old Digitech RDS1900 delays. They're 8-bit digital, no CPU involved, it's all logic and memory chips - does everything from flange to looping, with CV control. Nice and dirty, and grabbable for maybe 60 quid.
Compression on the cheap is another matter - I use an EHX White Finger on mono sources, it's a FET/optical unit in pedal format, is a bit faffy to set because of non-standard control labelling, but otherwise sounds good. Rack-wise, I have an ART Pro VLA ii, which is a dual-mono/stereo-linked optical unit, sounds good, is reasonably flexible but lacks side-chain, and the budget is given away by unpleasant switches, but hey, it's only about 240 quid.
The best spring reverb *emulation* I've used is the Boss FRV-1. I think that was about 79 quid. Does the job till I can work on getting a proper spring. Cheap spring reverb seems a bit thin on the ground, though you could DIY a case/supply for the Doepfer module. Or buy a tank and DIY the whole thing.
'Holy Grail' rack units are indeed ££££. Pragmatism demands mere £££, sometimes even ££. Yamaha's SPX 90 can be had for less than a hundred sheets, and for those of us who can't push to a Dimension D there's the Boss CE-300 for chorus. It's analogue (BBD), has just a mono in but stereo out, and some nice features like dry cut. Think mine was about £50 but they don't crop up much.
But you don't' care about that, because you have a Dimension D.
TBH I'm not bothered about classic pricey rack fx. I'm happy with stuff that has rough edges. I've ditched a load of pedals and a couple of racks and get a lot of use from Moogerfoogers. The Lexicon's my go-to reverb, I often use Logic's built-in compression for the sake of simplicity, and stuff like panning and widening can be done in software easily enough that I don't bother going out-of-the-box for it any more. I do like a proper analogue phaser and filter though, and EQ is channel parametrics on my A&H.
Also, get a MIDI Murf. Joy in a box!