I am not necessarily opposed to this. I just...
We start this episode (or end the last one) with Fingolfin being all...great! I finally made it here, and my people (mostly) didn't die, so now we're ready to go find Morgoth and that stupid half-brother of mine and let them know that we've got some axes to grind and we're not going away that easily!
So, there's all this forward momentum to go *find* Morgoth and Fëanor, and they've come a long way to deliver this message. So, we definitely will have Fingolfin get his point across to Morgoth. He's going to march up to the door of Angband, bang on it, and blow some trumpets. Sure, he's not ready to actually take the fortress, but he knows where it is and he has an army, (and the Valar and their light seem to be on his side) so the message there is pretty clearly one of threat (for later).
I think I would feel a bit...deflated...if we didn't continue on to deliver a similar message to the Host of Fëanor. I'm not picky about how we do that, though. I want there to be *some* clear indication of Fingolfin learning where the Fëanoreans are, and moving towards them with his entire Host. I want there to be some clear indication of the anger/tension in his camp (whether it's the reforging of Ringil, or moving into the oh-so-recently-vacated settlement of the Fëanoreans, or just sending messengers towards the Host of Fëanor without the viewers knowing what the message is.) I want to end with the feeling that we're on the brink of a conflict about to break out. I don't want to end with turning away from the gates of Angband in bewildered defeat without having a clear indication of what Fingolfin is moving towards.
But like I said, I'm not married to a particular geographical landing point for the two Hosts. Some level of 'now they both know that the other one is here' is probably all we need, and that could be accomplished without the two Hosts coming within sight of one another. But if we aren't going to have them eyeing each other warily across Lake Mithrim, then I want to make sure we have an idea of how we convey this sense of anger and threat from the Host of Fingolfin towards the Fëanoreans. That's all.
Alternately, if we really want to end the episode with the Host of Fingolfin right outside the gates of Angband, then we maybe need to deal with the Fingolfin-Fëanor tension earlier in the episode by having them march through Mithrim on their way to Angband. That would precipitate Maglor's move south, certainly, and might convey everything we need...but again, only if we plan that out. I don't want to save all of the intra-Noldor conflict for Season 4 Episode 1!