In my opinion, it is better for a new altcoin to adopt a fixed rate reward because of fast distribution. At the initial phase, a fixed rate reward will generate more coins compared to the percentage one because of the total block mined daily. It helps the project to mine more coin and distribute it to many people, what a new project needs in the beginning is a community. Wide and fair distribution is needed to protect the network and help the project.
If the coin in circulation is too little at the initial phase, someone will try to manipulate the price and it might harm the future of the altcoin.
Yes. Wide and fair distribution is the most important thing. Thank you for a useful information.