As far i know from Mr.spreads post, just having a MN is not enough to get payment, you may only shortlisted and that itself is dynamic because some one can easily counter it by putting more spr
Nodes will monitor time delays between receiving transactions and confirmations from masternodes and will assign scores for each masternode according to these delays. This score and deposit amount will affect which masternodes will receive payments.
so any one cry for true decentralization, think about btc ( check blockchain, lot of initial blocks with 50cns are mined by very few people with their cpus)