Counts as is fine in any game as long as the person on the other side of the table is fine with it. Just like with
GW games. People definitely do make their own characters, but their conceptual game identifiers matter.
What I usually do is try to integrate something about their name into the name of the new thing. For example, I wanted to include some Pirate stuff in my normal mercenary army but the nautical/pirate motif doesn't fit with where they've been operating in the story of local campaigns. So the "Sea Dog Deck Guns" become "Steelhead Field Cannons" and "First Mate Hawke" becomes "First Lt. Hawke". I used different miniatures for these than the ones
PP sell because I didn't like the pirate look for my army. I think the pirates look great, but I wasn't building a pirate army.
I also have a Khador army which is egyptian based using Wargods of Aegyptus miniatures and other Egyptian themed stuff from other companies. I call my Winter Guard stand-ins "Desert Guard." The Butcher of Kardov is still a big nasty brutish fellow, but he's no longer from some Russian sounding place. He's Atensekmeht the Butcher.
As for Mercenaries, they are very viable. And they just got even better with the release of the mk2 Mercenary Contract rules:
http://privateerpress.com/company/blood-and-coin-mercenary-contracts-for-mk-ii
I started playing when Mercenaries were not quite as viable as they are now. I went with Protectorate of Menoth and added Mercenaries and transitioned into playing Mercs and sold my Menoth stuff. There's no reason to start with another faction if you like the Mercenaries.
Army lists can have great variety as long as you avoid the group think that can go on in the various faction forums at Privateer Press's website. Some people get very vocal about what they think is bad and some people there post so frequently that you end up reading about how bad or good something is more often than you should given the size of the community. I'd recommend discovering what works for you in play.
Malfred's articles here on dakkadakka are astoundingly good for learning what works well together without having to run someone else's ideas for your list. Generally speaking, balanced lists are very competitive. Spend some points on jacks, some points on infantry and some points on solos and pay a little mind to how some things can boost the abilities of others and you'll be fine.
There are also some autoincludes based on the casters you choose. For example, Deneghra for Cryx needs arc nodes. And the three arc nodes are somewhat similar to one another so the core of a Denegrha army is likely going to include a few arc nodes. Magnus has a jack that only works with him. It's his only arc node and has one of the best one shot weapons in the game. He built the jacks with his bare hands and it's common to see him with at least one of them, often two. He's not as reliant on them as Deneghra is on arc nodes though.
The Protectorate of Menoth has some seriously good support units like the Choir and the Vassal. As soon as people start going jack heavy with Menoth, they're bound to show up as they're just so good with lots of jacks. That said, changing out Kreoss and some Exemplars for Feora and some Flame Guard and you suddenly have a very different feeling army even though they might both be running the same warjacks and support staff.
Armies can become superficially similar but remain fundamentally unique.
Let me know if you want to hear my thoughts on any particular mercenary item. I don't think any of them are bad. Even the much maligned Croe's Cutthroats have killed their share of warcasters for me.
Automatically Appended Next Post: Another thing that has happened as my mercenary collection gets larger and larger is that national faction casters and jacks that don't have a lot of faction only boosts become merc casters. For example, Lt. Caine doesn't really rely on having other Cygnar stuff around. All his spells help "friendly model/unit" so they're not Cygnar only. Some casters say "friendly faction model/unit" in a given spell.
So I can grab a caster and a couple jacks from another faction that work well with non-faction models and fill the rest up with mercenaries and end up with such an atypical army that people can be pretty shocked by it's uniqueness. And I can take Jack Marshals to run Mercenary jacks and have both Cygnar and Merc jacks in the same army.
An example:
Lt. Caine
- Sentinel
- Defender
Dirty Meg
- Nomad
Nyss Hunters
Boomhowler & Company
Reinholdt the Gobber Speculator