Good crypto data sources

Hi there! I'm doing a dissertation on crypto options and wanted to ask what the largest exchanges and best open source data sources were for spot and options.

Really would value insight from algo traders/researchers who have their own favourites. Of course as a student I am limited w.r.t. pricing.

I've had a look online and there are multiple lists looking at 24h volume, trust score and stuff like that. There's nothing on longer term volume so you'll sometimes see massive 24h volume on super dodgy exchanges I've never heard of.

Current ones I am planning to use: OKX, Binance, ByBit, Kraken.

They seem to have open source data that I can run some analytics on.

Paywalled but I wish I could find good data on: Deribit

Their data seems to be run through some paywalled site called tardis . dev which I can't use even though the data looks good there.

Are there any I'm missing?

Anyway thanks for your insight and time guys.