Being a good Jungler is hard.

I'm a low silver Vi main. My second most played champ is master Yi. Being low silver and having only played for just over a year and a half I can't claim to be an expert on League mechanics, but something specific has occurred to me about being a jungler.

Its REALLY hard to balance CS with lane pressure. Powerfarming with Vi and Yi is important because both champs damage scale well with items, but if one of my lanes really needs help I loose a lot of CS trying to help that lane. (but if I dont help them then they either feed or flame me). I can't get the power spikes I need from Trinity force, BOTRK, etc... It makes it extremely difficult for me to help my team midgame when I'm behind on Items, especially if the enemy jungler has had it easy farming up.

How do I tell my laners that I'm behind on Items/CS without being flamed for not ganking enough? How do I provide enough lane pressure without falling behind on CS/Items.

Should I help out only winning lanes to help me carry? Should I just ignore losing lanes and risk enemy champs becoming fed and carrying? Should I ignore all the lanes and powerfarm until I have my core damage items?

Maybe I'm just playing the wrong champions for the meta this season....