I highly recommend the RandomCampaignStart mod.  To start the game with the DangerBoat lance, you'll need to edit the Mods/RandomCampaignStart/mod.json file with the entries below.  (Do not edit the mod.json file in the Dangerboats directory!)

"Settings": {
  "RemoveAncestralMech": true,
 
  "NumberLightMechs": 2,
  "NumberMediumMechs": 3,
  "NumberHeavyMechs": 0,
  "NumberAssaultMechs": 0,
  "LightMechsPossible": [
"mechdef_panther_PNT-DB",
"mechdef_panther_PNT-DB"
  ],
  "MediumMechsPossible": [
"mechdef_centurion_CN9-DB",
"mechdef_hunchback_HBK-DB",
"mechdef_shadowhawk_SHD-DB"
  ],