What are your thoughts on rimmed or rimless cartridges that are more or less omitted?

For instance:
375 H&H Flanged (good round for single shot rifle; suitable for any African plains game and equally fine for double rifles e.g. for driven hunts)

400 H&H (well thought cartridge for DGR without undue recoil; enables very smooth feeding)

450 Rigby (the alternative to 458 Lott; the case is capable of more…)

500/416 NE – surprisingly flat shooting rimmed round for a single shot or double rifle intended for DG

CZ