As others post, insurers may require the MCBs be used in place in of fuses to greatly reduce the risk of the wrong size OCPD being used.
Otherwise, no problem in useing fuses.
I would however be rather concerned at the use of glass fuses. Are these cylinderical glass cartridge fuses, with the fuse wire visable within ?
If so, they are probably unsuited to branch circuit protection, and pending any major upgrade, the glass fuses should be immediatly replaced with ones listed for the purpose.
Here in the UK glass fuses have only very low interupting ratings and can fail explosively if subjected to the fault currents likely to be found.
One brand has a maximum interupting rating of only 10 times the normal current, that is a 15 amp fuse can only safely interupt a fault current of 150 amps.
Other types are only intended for vehicle electrics and similar, not for line voltage.
Ceramic bodied fuses filled with sand or other materials have very much higher breaking capacities and are suitable for virtually any likely fault current.