Well, Operation The Ultimate Frontier was said to be harder than Newport, with some even going as far as to say it's harder than the Halloween Ops....

I've 5 star'd it SEVERAL times now. So in truth, what they were saying, is they are plebs.

For Battleships:
The ship I have been using most is Nelson. She excels at this one, with HE that absolutely DEVASTATES what it hits, easily doing 8-10k a salvo against the BB's and citadel'ing CA's. Her heal, well, she is a T7 Conqueror there.

I find her much better for this Op than Scharn, seeing as her dispersion is considerably better with much stronger HE and better AP. She can tank quite well and her secondaries are proving to be better than I originally pegged them for. She also doesn't catch fire nearly as much as Scharn.

If you don't have either, KGV is a very good option with CO doing well here as well (at least for me.

).
For Cruisers:
I've been drifting between them all. Myoko's turret traverse is a pain in this one, though she can be very devastating if you don't forget that (I kinda forgot about her horrid turret traverse

). Fiji is a very good option (and mine is full stock) with Belfast possibly being a stronger one due to HE with her. Yorck and Shchors are okay, but I really can't say as they are both full stock still. Play more supportively if yours are stock and chime in if they are elite.

Penny will do well here as well. Play her properly and you'll find yourself raking in the credits.

Atlanta is a strong contender here, though make sure you have AFT or you'll regret it, big time. Indy did quite well for me, but I've only used her once. I just used her like Penny.

For Carriers:
This is going to give you nightmares. DF is on all the things, DD's included. You'll need to be very selective of what you hit, or you'll be out of planes before the 1st phase finishes. Do NOT use anything other than "Strike". You are wasting a slot if you take AS. Reason: Raptor will NOT attack any ships with the exception of any vessel within a certain distance of her (so far it looks to be sub 10k of her). All of her bombers hit the base otherwise and she only has DB's, so no need to worry bout TB's. And to top it off, I've only seen her hit the base 3 times with two attacks against a fort and the last one against the Power Station and Warehouse which are not mission critical. If you can, divi up with someone so they can take out the DF ships quickly. Since they are all USN ships, you'll easily know what has DF. *
There is only one exception to this, a NO, which sometimes shows up (not all matches I've seen her). I haven't seen her use DF. Kaga is a very solid contender so far, with having SCORES of TB's to use. Hiryu is also a good option. Ranger and Saipan are slightly limited here however. Ranger suffered with her "new" loadout, having less bombers than what I remember, specifically her TB's. Make damn well sure of your target when you commit them, as you are likely to run out before match end. Saipan is slightly better off, but not by much. Her plus comes in fast planes and two fighter squadrons, which helps in keeping DD's spotted. But her planes drop like flies if you are not careful. T9 my potato. Feel like T5's to me.

For Destroyers:
I've yet to use a DD here, but Sims is a common one with Mahan being another. Should be obvious why.

There are two ships that MUST be dealt with or the op will fail outright once the transports start coming in, A Cleveland and Atlanta. There is also the Pensacola that should be a high priority. Make sure those three are dealt with before the planes start coming in. If the Transports fly over either the Atlanta or Cleveland, you've failed (unless someone nips the quickly enough) as they will shoot down the transports quite quickly. Penny is in the air, as I've seen them get through half the times. The times they got through, Penny was raked with HE by other ships. With the Cleveland and Atlanta, it won't matter. Either sink them or fail the op.
As a Cruiser, push north to quickly deal with the Cleveland and Atlanta (who spawns a couple mins after Op start), then focus the Penny if she's not down yet. Do NOT chase after DD's. As a BB, stick reasonably close to the base and try to take out Penny when you spot her. Raptor is in H2 throughout most of the match, ignore her. You'll eventually have a "natural" chance to engage her. Otherwise, the Op is easy to read. The make or break is in the opening stages, usually. I've seen a lot of teams fail in the opening, which is sad. Had a team so bad an hour ago, that there were only 3 of us left after the first 5 mins. Two BB's (myself in one), and a Cruiser who had a brain. That was an intense match, which sadly ended in failure (we came real close too).

EDIT: Make SURE you hit any ship getting too close to the aerodrome. I've seen a DD take it out in 3-4 salvo's, it's that weak.
*EDIT2: NO does have DF. She didn't use it the last couple of times I attacked her, but definitely this time.