Hi!
Barans are a different beast than usual armies. They are actually masters of being sieged. With STR 1 you must position your units for taking blow first then retaliate.
In the latter the Baran is quite good, as almost all their base formations are able to shoot over half of the table.
Their firepower are low (until you start shooting with TK weapons), but so many shooting attack will easily break enemy formations due to blast markers, regardless of armour.
Their movement speed is their biggest weakness! Against a careful opponent you will probably end up with formations moving no more than 15 cm at TURN 3 and are away from objectives. Marching whatever you have, -even infantry- is a key to compensate.
Siegfrieds: Their speed and numbers makes them a durable scout and very important for grabbing objectives! Your priority with this formation is to keep them alive and slowly position them to reach multiple objectives at your opponent table. Fighting is optional.
Ragnaroks: Note that they are allowed to be placed in garrison. 60 cm battle cannon in overwatch from the very beginning is quite good. They also physically able to defend garrisoning infantry next to them, with armour and fire support. Make sure you save one commissar for this formation as fighting on the front and soaking up fire, is their main objective.
Infantry: They have 3 roles which depends on their upgrades. Without upgrade they are cheap activation boost and objective hunters who are marching from cover to cover. [A bunch of AP6+ is not a big loss anyway.]
Thudd gun is perfect for your HQ infantry staying behind frontline (perhaps taking the role of blitzguard) and still giving potent artillery fire. Regular infantry thudd guns may be placed forward to generate suppression at enemy ranks right in their deployment zone!
Rapier destroyer grants your infantry a decent anti armour firepower. Forward garrisioning is highly advised.
Additional infantry is not useful to take. If you want to build up your HQ -forced BTS formation- you better take guns, hellhound, snipers etc.
The rest is up to you to try what suit your playstyle the best.
CHeers