The reason you could find a Julie London LP in mono is because most of her work was done in the mono era of LP production (early 50s to mid-60s). I very much doubt that you can find mono recordings of the artists you list in your last sentence, because they are very much with us in the here and now, in stereo. I have some Julie London mono LPs; I agree it works well in mono. But I would not agree that you need to limit yourself to solo performances; most small group jazz and chamber music does very well in mono, and somehow the brain picks up spatial cues from mono surprisingly well.
I thought at one point in reading your post that you were going to ask about listening to mono through one speaker of a stereo pair (assuming your system is basically stereo), vs listening to a stereo pair of speakers each of which is reproducing the same mono signal, simultaneously. Anyway, I take the latter approach. Then there is the endless debate about using a mono cartridge vs a mono switch on your preamplifier, or both. It is true that mono signals are generated from lateral movement of the stylus, exclusively. Vertical motion generates noise from the LP groove, only. Whereas true stereo reproduction requires that the music signal is encoded in both planes. Thus stereo cartridges tend to reproduce noise from mono LPs, and many think that using a mono cartridge or a mono switch is the only way to go. (Either way, you are cancelling the signal due to vertical motion of the stylus by bridging.)
I thought at one point in reading your post that you were going to ask about listening to mono through one speaker of a stereo pair (assuming your system is basically stereo), vs listening to a stereo pair of speakers each of which is reproducing the same mono signal, simultaneously. Anyway, I take the latter approach. Then there is the endless debate about using a mono cartridge vs a mono switch on your preamplifier, or both. It is true that mono signals are generated from lateral movement of the stylus, exclusively. Vertical motion generates noise from the LP groove, only. Whereas true stereo reproduction requires that the music signal is encoded in both planes. Thus stereo cartridges tend to reproduce noise from mono LPs, and many think that using a mono cartridge or a mono switch is the only way to go. (Either way, you are cancelling the signal due to vertical motion of the stylus by bridging.)