Welcome back @technome I expect others will have valuable things to say here. I am researching this a little, to see if I can help. 29,000 cards is a lot, If you moved this into a structure like a CSV where the columns are named rather than needing to repeat key/value pairs, but as far as I can tell you would have to construct your own lookup, perhaps having the key/name in the first column. But you may be able to divide this data based on one of the other values.
- Why is it in this format in the first place?
- Have you tried JSONMangler? I am trying to find a source
- Erics Rerelease of SaveAs may provide useful later moving these as tiddlers to a Plugin.
- Some time ago we got good performance on a wiki with 60,000 tiddlers, but a few tweaks were needed to avoid accidently itterating all the tiddlers eg; in sidebar recent tab.