27" should be minimum unless hard capped by physical space limitations.
Even if you can compensate 24" smaller size by moving it little closer for same effective size, that shorter distance is harder for you eyes.
(focusing to closer distance is more stressfull for the eye)
Also monitor selection of 24" size is poor.
This MSI would be one of the top choises in 27" 2560x1440 IPS monitors:
MSI 27" MAG274QRF-QD 2560x1440 IPS Quantum Dot 165Hz 1ms FreeSync/G-Sync Widescreen LED Backlit Gami=
£498.95
Response times are very fast and also contrast of AU Optronics panel is very high for IPS, unlike substandard contrast of LG's 27" 2560x1440 "Nano-IPS" panel.
Also AdobeRGB covering colour gamut is very wide giving punchy colours for games.
G273QF would be basically older version of the panel with DCI-P3 gamut.
MSI OPTIX 27" G273QF 2560x1440 IPS 165Hz 1ms FreeSync/G-Sync Widescreen LED Backlit Gaming Monitor=
£348.95
Though stand lacks basically all adjustments.
Again 32" size has less competition in 2560x1440.
Though that size LG's Nano-IPS panel (DCI-P3 gamut) has normal for IPS contrast.
LG 32" 32GP850-B 2560x1440 NANO IPS 165Hz 1ms FreeSync/G-Sync Compatible Widescreen Gaming Monitor=
£449.99