Localization to delocalization transitions in eigenfunctions are studied for finite interacting boson systems by employing one-plus two-body embedded Gaussian orthogonal ensemble of random matrices [EGOE(1+2)]. In the first analysis, considered are bosonic EGOE(1+2) for two-species boson systems with a fictitious (F ) spin degree of freedom [called BEGOE(1+2)-F ]. Numerical calculations are carried out as a function of the two-body interaction strength (λ). It is shown that, in the region (defined by λ > λ c ) after the onset of Poisson to GOE transition in energy levels, the strength functions exhibit Breit-Wigner to Gaussian transition for λ > λ F k > λ c . Further, analyzing information entropy and participation ratio, it is established that there is a region defined by λ ∼ λ t where the system exhibits thermalization. The F -spin dependence of the transition markers λ F k and λ t follow from the propagator for the spectral variances. These results, well tested near the center of the spectrum and extend to the region within ±2σ to ±3σ from the center (σ 2 is the spectral variance), establish universality of the transitions generated by embedded ensembles. In the second analysis, entanglement entropy is studied for spin-less BEGOE(1+2) ensemble and shown that the results generated are close to the recently reported results for a Bose-Hubbard model.