Subscribers voices need to be heard more than the Mods
Change mods chat streams. It's best for the subscribers to be heard more in chat. Mods should only monitor the stream and whisper to streamers who are out of hand. Not to personally chat through out the stream. Also not to get involved in streamers activities.
Streamers often pick their moderators out of the community. Moderators often are long term community members and well known to the streamer. The streamers knows on how they behave and have a certain degree of trust in them. Often streamers and their moderators have met before, for example on community meetings, TwitchCon etc. In many cases streamer and their moderators are even real-life friends.
I understand your concern that streamers in certain cases put a lot of attention on their moderators. As mentioned before that's often because of the trust and friendship between them.
Not to neglect other chatters is something the streamer should of course do, but that depends on the streamer and you cannot enforce it. If the streamer of your choice doesn't take enough notice of you, it might be that you put too much personal feelings in it. You know what I mean, don't you?
Also, at this point I want to bring out that you only mentioned subscribers. For sure subscribers support Twitch and the streamers "more" than non-subscribers. But as a subscriber you haven't payed for a special treatment nor for a special portion of the streamers attention.
Exceptions prove the rule, but that depends on the streamers.