Gutierez is great, he just works hard defensively, though he's been pretty poor this season but pretty much the reason your left backs have looked decent for the past 3 years. Obertan should go, offers nothing, Marveaux hasn't looked bad but is only just coming into the team after a long/bad injury, he looks decent but has had games against mostly poor opposition IIRC so bit tough to judge how he'd be in big games and week in week out.
Remy, at the moment Cisse having lost his form has been mostly switched with Ba and playing the wider/deeper role rather than upfront with Ba wide left like last season. Not much choice with Cisse being no where near form he had to push Ba upfront to let someone get goals. Cisse, its tough, who really predicted that severe a drop in form. While people bang on at Pards because its a tough spell, you deserved a draw against City for that second half and if Cisse had any form at all he'd have gotten at the very least 1 to draw level and maybe more. Someone to play ahead of Obertan(who just isn't good enough) and someone to let Cisse be rested IS what you need.
Likewise with Ba on the form he's been in for 2 years, you can't realistically hope to hang on to him, thats life with ANY club. Strikers move on from utd, Real, Arsenal, Liverpool, Barca and Newcastle aren't magic you can't never buy another top striker and pretend Ba will never leave, if you do, when he leaves you'll be screwed.
I think Ba should and probably will stay till the end of the season, but what you want is someone to get some games, let Ba rest, let Cisse rotate in and out, give Cisse some real competition and hunger(would any manager drop him long term for Ameobi.... lol ). That way if Ba goes in summer which I see as likely you both, have a striker who has 6 months in the team, and hopefully some form. Otherwise you start next year with no form striker and hope anyone you buy can come in firing, if not, you're screwed again.
Remy would make sense if you keep Ba or if you sell him. That would only be 3 "proper" strikers, give Cisse some motivation to get back to form, and cover, what happens if Ba gets injured between xmas and the end of the season?
It's not the only thing Newcastle need, but they definitely need a third real striker, neither Ameobi cut it, at all, nor Ranger(if he's not in jail).
You do need a third striker, but you also need a top CB and a top fullback, the guy whose name I can't remember, starts with a G i think, scored a cracker, and Anita have both at points played at right back, but both seem better in central midfield. Not convinced of Anita but you never know, you've got numbers there. You need a CB to help with injury issues, and someone who can play more in the Cabaye role as cover.. though Marveaux looks promising there.
Shame Dalglish & Comolli are no longer there!