This really depends.... firstly the whole point of freestyle for begginers is so they learn new moves off others... i learnt most of the moves i know this way... however.
The very good guys i know can take a begginer and help her complete almost any move because their lead is so good - i remember dancing freestyle after just 1 lesson because i understood the lead... if you're questioning your lead then perhaps it's best to stick to moves they do know.
Try dancing with a more experianced girl and asking her how good your lead is, she may recommend you try new things with begginers and at the very least can probably give you pointers on your lead.
For me the most helpful lead is one that's not too 'Memememe ie. too strong as this frequently unbalences me, i can spin perfectly well on my own etc...' but one which does for example, push back more strongly with one hand than the other so i know which way to step back.... always hold out the hand they want me to take clearly as opposed to just grabbing mine etc..
Basically try not to unbalence the girl and use verbal cues where necessary.
...and ask a girl to give you pointers...

Was that even at all helpful? I waffle. I just know that a good lead is always welcome to do new moves but a poor lead doing new moves is frustrating.