You may want to visit
http://pullmyfinger.wikispaces.com/home, the unofficial Malifaux fan wiki. There are a number of useful articles about getting started, including which starters can be played as is, and which one need added blisters. Another useful article is the one about which masters are good for a first crew and which are not (Leviticus, Pandora, and Collete are the ones who come to my mind right now).
Also, a visit to the official Malifaux forums is helpful:
http://www.wyrd-games.net/forum.php
Regarding Kaeris, I do own her boxed set although I haven't played it yet (never mind prepping them for painting ...). Kaeris is a Arcanist Henchman, and Henchmen have certain hiring restrictions that Masters do not.
IIRC, Kaeris can only hire
MSU members and
MSU assets (and the Fire Gamin). This isn't to say that a Kaeris-led crew cannot be effective, but you will have a smaller selection of models that you can legally hire (pretty much the box set plus a few other models) as compared to a Master (like Ramos, Rasputina, Marcus, or Collete).
Right now she can hire:
Joss [9ss]
Renegade Steamfitter Johan [6ss]
Gunsmith [6ss]
Soulstone Miner [6ss]
Large Steampunk Arachnid [5ss]
Fire Gamin [4ss]
Union Miner [4ss]
Edit#1: Iggy, a fire-themed Neverborn Outcast who has Affinity(Kaeris), also from Book Three.
Of the above, I have used Johan, Gunsmiths, and the LSA although with Ramos or Rasputina, not Kaeris. Gunsmiths are both useful and versatile figures, and Johan is a tough all-rounder but is slightly better in melee. Johan does get a +2
Cb when within 3” of another friendly M&SU Member. The LSA has been lackluster; it's simply not as durable as other Arcanists constructs.
Since I have not fielded any of the other figures yet, I won't comment. Visiting the wiki should give you pointers on most of those units.
Now my first master as Rasputina and my second Ramos. Of the two, Kaeris will synergize best with Ramos. Kaeris and Rasputina both use lots of Soulstones and while they can be run together, you will use your cache quickly. Ramos usually doesn't use too many soulstones, so Kaeris can use the cache instead.
If you decide to pick up the Ramos boxed set, I'd suggest getting the Electrical Creation, the Mobile Toolkit, and perhaps Johan. The former is needed because Ramos can summon it and it is a flying bomb which can give opponents a fit when used correctly. The Toolkit is necessary since Ramos is so Tome-dependent: it gives him (or another target model) a Tome, making sure Ramos can summon new spiders or the Electrical Creation.
With Rasputina, my suggestion would be to ignore the box set as the Ice Golem is not an useful figure. Get the Ice Gamin, a Silent One, the Essence of Power, and Taelor. Taelor is a 8ss Outcast Mercenary [9ss when hired out of faction] but she has Hard to Kill, Hard to Wound 1, Lifer, [+1] Melee Expert, and a Magic Hammer (does full damage against spirits). Her Hammerstrike action can be used to boost Raspy and the Ice Gamins' glacially slow movement. The Ice Golem also costs 9ss, but does far less than Taelor.
Collete is a finesse master and not a good starting choice. One needs a strong understanding of the game mechanics before playing her. Marcus is considered the weakest Master in the game. He has almost zero synergy with any figure and all the best Beast choices are out of faction, so he pays more. The only local player who uses him (and that rarely) takes him with Kaeris. Since Marcus is the Master, you can hire anything you like ignoring Kaeris' hiring restrictions.
Good luck, and remember, in Malifaux, Bad Things Happen.