The MCB has a different curve to a fuse, so adding a fuse to a circuit already protected with a MCB is often a waste of time as the MCB will still trip first. In the main with lighting circuits it is the ionisation of the gases in the bulb which is the problem often seen as a flash when the bulb blows, inside each bulb there should be a fuse, and this fuse should blow before the main one for all the lights, when lighting circuits had fuses this worked OK, but when we went to MCB's often the MCB would trip first. So on a lighting circuit any fuse over one amp will likely never blow so no point in fitting them.
The idea of fitting extra fuses is so with a fault you do not lose all lights, with outside lights you have a chance of water ingress, so either a double pole switch or a switched fused connection unit (FCU) is often used so if there is a fault the outside light can be isolated allowing rest of lights to still work. Also the fuse carrier of a FCU will take a lock, so you can remove the fuse and lock off the circuit.
It is all down to you what you fit, for example with office lighting with a suspended ceiling it is common to have lighting track and every light plugs in, that way the electrician can work on one light without switching all the lights off, this is hardly required for home use.
The ELV lighting seems to be losing favour today, it had two advantages one being when used in bathrooms so no LV lights, and two when using quartz lamps it extended their life, today it's a pain, as harder to convert to LED and the replacement quartz lamps will in time become harder and harder to get. I would think twice before fitting ELV lamps, if there are LV versions better to use 230 volt.
