I saw a video where a fellow had a large flock of mixed breeds and just one SLP in the flock. He sat in his chair to watch chicken TV and the little SLP jumped on his chair to talk to him and he would talk back to her - cutest thing. It's good that you have two Polish instead of just one like the fellow did. The Polish are gentle natured and mixing them in a Heavier LF flock is just not what I would do. Your chicks may be skittish now but give them time. Once they learn who their feed and treats come from they'll be eating out of your hand. Wait for them to approach you rather than reaching out at them. Gentle natured fowl are skittish as chicks.