Multi-beam spot diffusing optical wireless systems have been shown to offer performance improvement compared to conventional diffuse systems. In this work, the authors build on the genetic algorithm multi-spot diffuse technique [1] by adaptively optimising the power distribution among the radiating spots. Our goal is to reduce the effect of intersymbol interference and to improve the signal-to-noise ratio (SNR) when the system operates under strong background noise and multipath dispersion. This method can deliver superior SNR and delay spread results compared to other existing systems. This paper also examines the boundaries of the maximum SNR that can be achieved in an indoor wireless system. It is demonstrated that the SNR can improve by as much as 50 dB compared to conventional diffuse systems paving the way for faster and more power efficient communication links.