In book 1 the following have caught my eye:
The Changing Game - This page looks at long term campaigns, long term goals and ambitions, and the changing nature of high-level adventures and campaigns - it could be much more than just going deeper into the dungeon to kill bigger monsters:
- Settling down and establishing strongholds
- Wide-ranging exploration
- Becoming a political player, or at least a force that rulers will be aware of
- The Planes of Existence
- Paths to Immortality
Bastard Sword - I would allow dwarves to use it two-handed but not one handed, but probably not let halflings use it at all.
Blowgun - This weapon is reliant on poison, which brings up questions of ethics and game balance. I would expect those who use blowguns to start making checks to handle the poison correctly
Heavy Crossbow - I would say too big for halflings, but dwarves could cope with it
Net, whip and Bola - The Entangle/Slow/Delay effects offer interesting tactical options, though I am not sure about the effects being so dependent on target's level
Unarmed Combat - Better than in the 1st Ed AD&D DMG, but I'm sure a lot of DMs will want to at least tweak these rules, particularly in non-standard situations
Strongholds - I liked this section as a good introduction to players owning and maintaining their own places. One thing that crossed my mind was there was no mention of surviving, loyal henchmen from dungeon expeditions being offered good positions in a stronghold "Bob, you've served me well in our times together in the Caverns of Chaos. Want a cushy position as the captain of the guard at my castle?"
It's interesting that the expected wages of some of the castle staff are quite expensive, thus prompting either further adventuring for loot, or else careful government of the PC's lands to generate tax revenue.
In Kaelaross I can well imagine powerful PCs setting up their own strongholds, or perhaps being asked by a ruler to look after a borderland village or keep that is proving troublesome or vulnerable to attack. Imagine if the town council of Ironmarket asked the PCs to capture Charsis - in return they get to govern it.
Character Class Descriptions: This half of the book gives some straight-forward extensions for human character classes for levels 15-25, including experience needed, spells per day, improved thief skills and the like. There are also spells for levels 6-7 for clerics and 7-9 for magic users. All of this is a no-brainer for inclusion - of course it's accepted as part of gaming in Kaelaross. Heck, it's the basic reason for the Companion Set's existence - everything else is optional add-ons.
Interestingly it offers all human characters a choice - settle down and set up a stronghold (see above) or wander around the campaign world. Wandering around offers further options for each class.
The Druid is introduced as a proto-prestige class - once a neutral cleric reaches 9th level he may choose to undergo the training necessary to become a druid. I like the idea that druids can't use metal - only leather, wood, stone and bone. This could lead to some interesting magic weapons created by druids for druids.
I am not sure about actually having druids as part of Kaelaross - it could be more of a step away from the B/X feel than I am prepared for yet. I won't say never, but I will say not yet. Haaken is a deity I created as a possible patron of druids, so if I did introduce druids, he would be the one to instruct them.
As for the druid spells, I might consider Haaken granting them to his conventional clerics in exceptional circumstances.
Wandering Fighters have the options of becoming knights, paladins or avengers. Like the druid, these are proto-prestige classes, with quite a few abilities (casting clerical spells) and roleplaying restrictions (loyalty to a liege).
I'm not sure I would actually have these as part of gaming in Kaelaross, at least not as written. I've already written about orders of knights in Toutus, and I view knighthood as something to be roleplayed rather than additional abilities to be min-maxed. Offering intrinsic benefits to a fighter who is roleplayed as a knight as opposed to one roleplayed as a gladiator, a professional soldier, a bodyguard or a barbarian does not sit well with me.
Magic Users - I'm amused by the bit about PC magic users settling down and building their own dungeon and inviting monsters to move in! However, I do not take this very seriously, and if any of my PCs tried this, I don't think I'd let them get away easily with "farming" the dungeon for looted treasure. The note about Magists being the wizard-in-residence at a powerful NPC's stronghold is an interesting alternative to the mage maintaining his own domain. Perhaps this could be applied to other classes (a PC cleric becomes a resident Chaplain, a PC fighter becomes a resident Marshal of the Guard, a PC thief becomes a resident Spymaster?)
Thieves similarly have the opportunity to either become guildmasters in a town (their equivalent of settling down into a stronghold) or else wander around as a rogue (interesting use of an over-used name).
Demihumans in the Companion Set have reached their maximum levels. And here things aren't so adaptable or suited for adventuring. The book talks about clan relics, but I can't really see these being very useful as they can't be carried around in your backpack into the dungeon or wilderness. They also seem quite specific - not exactly world-specific, but each race has just one possible clan relic, and there isn't much leeway offered to DMs or players wanting to do something different with top-level demihumans.
Because I have added new classes for demihumans in Kaelaross (namely the Dwarven Cleric, the Halfling Defender and the Elven Ranger), and also added extra levels to "standard" halflings (known in Kaelaross as Halfling Scouts) I am aware I have already sort of interfered with the Companion set's ideas of what demihumans should do at this level. The spellcasters (particularly dwarven cleric and halfling defender) make clan relics sort of redundant, or at least can cast spells that are similar to the relic's effects.
The additional attack ranks and special defences are worth bearing in mind, and if any demihuman PC reached top level and continued to keep track of XP, I would allow them these extra bonuses as some compensation for their level limits.