Has anyone ever created this type of house rule?
Yes.
Oh, you want specifics? Well I'm not familiar with MegaT so I don't know if the details will work but here are some of the concepts I've seen used in games or discussed here or on other Traveller sites.
1) Skills increase based on usage.
1A) Roll a 12 on a skill task (based on 2d6 roll high to succeed) and the skill used goes up.
1B) Roll a 12 on a skill task (based on 2d6) and the skill used has a chance of going up. Roll 1d6 and if the result is > the skill level, you gain a level.
1C) Roll a 12 on a skill task (based on 2d6) and you gain points towards leveling up.
I've seen derivatives that
- believe a roll of 2 on a skill task (based on 2d6) indicates 'learning from your mistakes'
- have detailed book keeping with every task roll being documenting and counting toward some amount that must be reached to level up.
2) Skills increase based on time. Several Traveller systems have built in methods of training up skills. From what I've seen, this is usually a system that determines the amount of time it takes to train a skill level. Some people running a campaign simply provide down time between adventures so that characters can gain skill.
3) Point buy system. Ran across this on one of the forums recently. In MongooseT, one of the optional character generation methods is a point buy system. At the end of each game session, the players get a point and they can spend or save points to buy skills and characteristics based on the predefined point buy system.
- you could assign points based on degree of success
- you could assign points based on good role playing
I know you don't want to hear about how Traveller characters start at a high 'level' compared to D&D or other games in regards to arguing against a leveling system. I point it out though for the following.
- Consider how long it takes a 1st level D&D character to level up compared to a 8th level one. Should a Traveller character that has the numerous skills of 6 terms of service (essentially a high level character) be treated differently than a character that has fewer skills from only 3 terms of service. (essentially a mid level character)
- Personally, if using a system that has fairly fast 'leveling' I would severely limit the # of terms for the starting characters to possibly only 1 or two terms so that they start out like in other games as newbies and the added skills they get early on have a much greater benefit.
I've often thought of starting a game where there is no chargen other than characteristics and all the characters are 18yo.