Small or Big pool does not matter, it will average out over time. Help the network by spreading the hash to a small or medium pool.
Check pool size here: [https://wwwpoolexplorer.rvnstats.info/dcom/TcDzUYmmzcoin/x16r-ravencoin-mining-pool-statistics-v1-3 Rvnstats 3340 PoolExplorer Pool list]
A good recommendation when choosing a pool is any pool not in the top 3 highest hashrate, but any other pool with at least around 0,5% of network hash rate so the pool will hit some blocks each day. Or if we want to help build up a tiny pool, go for an even smaller one.