Well, I'm not a Retribution player, but I'll give it my best shot
Firstly, I generally don't recommend theme lists or spam lists to starting players. Some can work, the Rhan theme list is actually pretty nice generally, but it gives you a very narrow set of options that don't always work well with other casters, and having a variety of different options is often better to get a broad feel for the game. The Rhan list, in particular, is only legal because of his theme list, so there are 2 units of them that you would never be able to take in any other list. If anything, only take Rhan's list to tier 2 or 3, get the free Arcanist and leave the redundant units of tier 4 until later. He can also take Houseguard units, so a unit of Houseguard Halberdiers might be a good idea, as they make better front line troops to take charges and keep your Battle mages from being tied up.
As mentioned, outside of a few specialized casters, running more than a couple of jacks becomes difficult because of Focus limitations - Jacks need focus to perform at their points level. Jacks are more like... specialized problem solvers. They are power at a point, a point upon which the game may hinge that is, with the option to boost and power attack when needed and they're fairly sturdy, but it's still infantry that do the general fighting duties in most lists. If you want more jacks you can always try marshaling one to a unit of Dawnguard sentinels (but only with the U/A who has Pronto), though obviously that wouldn't be in the Rahn theme list.
A few general suggestions though - consider picking up the battlebox set, just for learning on. Kaylssa isn't bad, and you'll get a bit of use out of the jacks. Secondly, consider trying to magnetize the heavy jack kits that you get (and the heavy in the battle-box if you get it), so you can have a selection of jacks when you want it.
. Thirdly, start small. 15 and 20pt battles while you learn the ropes is fine
It's all in the name.
Looking for a club in Brisbane, Australia
? Come and enjoy a game and a beer at our friendly club in a pub, Sunday nights from 6:30. All brisbanites welcome, don't wait, check out our Club Page on Facebook
for details or to organize a game. We play all sorts of board and war games, so hit us up if you're interested.
Update:From the 25th of May 2014 we'll be Meeting at The Junction pub in Annerley, opposite Ace Comics and Games
Still playing 40k, Warmachine and board games of all sorts!