With the excellent advice given on this forum I've decided to make some changes to my Chapter and it now stands like this. All comments are naturally welcome.

Name: Smoking Fists

Why was the chapter founded: Counter against Orks

Foundation: 41st millennium

Progenitor: Imperial Fists

Gene-stock Purity: Pure (as pure as Imperial Fist gene-seed might be, at least)

Missing Zygotes: Betcher's gland and Sus-an membrane

Codex Demeanours: Swift as the Wind

Characteristic Modifiers: +5 Will and +5 Ag

Founding Father: The very first Chapter Master was a tank commander of some reputation from the Imperial Fists. He lead the Chapter on a ramage against the greenskins with thousands of the foul creatures crushed beneath their tracks. A great deal of the present customs of the Chapter have their roots in these campaigns and his leadership.

Current Chapter Master: Engwal, a fine warrior and leader presently leading the Chapter in the Jericho Reach where they have fought many successful tank battles against both Tau and Chaos forces, although with many fallen brothers as a result of their commitment.

Homeworld: Trawyck, a former War World which has now been turned into a feral world dominate by vehicle-mounted warrior tribes scavaging what they can from each other and fighting for what resources that can be found among the blasted ruins of fallen cities.

Relation with World: Distant Rule, the Chapter watches from range and only intervienes to stop major technical or societal advancement that could threaten the current chaotic situation

Organization: Codex Chapter, although the Chapter has through ties with the Adeptus Mechanicus manage to have a slightely larger vehicle pool than most other Chapters

Combat Doctrine: Codex Combat Doctrine but favoring amoured assaults when possible

Chapter Deamenor: Swift as the Wind

Solo Mode Abilites: Iron Steed, the Battle Brother can re-roll any failed Drive test

Squad Mode Attack: Tactical Finess (see Rites of Battle p. 33)

Squad Mode Defensive: Hold at all costs (see Rites of Battle p. 49)

Primarch's Curse: Death before Dishonor (see Rites of Battle p. 48-49)

Pasts: Jericho Reach Veteran: You have already once serve in the Jericho Reach with your Battle-Brothers and now you stand ready to do so again againt what horrors it can throw at you

Amoured Champion: You and your brothers engaged the greenskin land armada outnumbered fifty-to-one but in the end the sky was chocked with the black smoke from the burning machines of the Xenos

Survivor: Your tank was destroyed and the crew slain but you made it on, and several months later rejoined Imperial forces despite the enemy's best efforts to destroy you

Armoured Fist: You fought with distinction to break through the enemy's lines and destroy their armored counter attack

Tank Hunter: Through a grey and blasted landscape you stalked the enemy's amored vehicles and destroyed them one after another, leading to their dislodgement form the city

Names: Albrecht, Talwas, Erwin, Gerold, Sigfried, Torald, Sigmid, Lothar, Max, Wez

Beliefs: Revere the Primarch

Chapter Current Status: Under Strength - three companies including the First Company have come to take part in the war for the Jericho Reach, and a fourth company has been sent for, despite heavy losses already suffered the Chapter is determine to make their first crusade into a victorious one

Chapter Friends: Adeptus Mechanicus

Chapter Enemies: Greenskins

Chapter Trappings: Ossific Relic (see Rites of Battle p. 51) and Scrimshaw Tools (see Rites of Battle p. 51)

Chapter Relics: Erwald's Bones (a ossific relic from the first brother to serve in the Deathwatch and who also fell in that service) - gives +10 in WS, BS and Will to the bearer

Custom Advances:

Tactics (Armored Assault) - 200

Tactics (Armored Assault) +10 - 200

Tactics (Armored Assault) +20 - 400

Drive (any) - 300

Drive (any) +10 - 400

Drive (any) +20 400

Nerves of Steel - 400

Hatred (Orks) - 250

Peer (Adeptus Mechanicus) - 400

Eye of Vengeance - 500