I'm a huge fan of both Mekton and Battletech. Both are great games, and I've been eagerly awaiting the completion of the Mekton Zero Kickstarter for literally years. It was expected to deliver in 2014... and we're still waiting...
In the meantime, I've been giving some serious re-read to the Mekton material in hand. Specifically, the advanced construction books, Mekton Techbook for the Mekton II edition, and Mekton Zeta Plus for the Mekton Zeta edition. The latter is a revision and expansion of the former, but lacks the extremely interesting and fun listing of mecha from the Archipelago War on Algol. As I've given these books a thorough re-read I've found things I prefer to Battletech and things that Battletech might just do better. For example, without adding a Ground Effect System or similar to a Mekton, it's impossible to get the spread of land movement speeds that are evident in Battletech. The ability to jack the basic running speed of a 'Mech up to the crazy levels of a Locust or Hussar just don't exist in Mekton without adding something better than plain old legs. This, I think, Battletech does better.
On the other hand, Mekton has something in place to fix a problem I've long had with Battletech. The fix also reveals perhaps why Battletech doesn't deal with it. I'll elaborate. Sitting in front of me is a pair of 25-inch flatscreen monitors. Ten years ago, these monitors would have been about five times more expensive, and a bit bulkier. Twenty years ago, they'd be CRTs that would have so much depth to them they wouldn't fit on my desk. Plus, the screen size would have been something only design drafters or professionals in the electronic art industry would have even had access to or been able to afford. As technology marches on, established technologies tend to get smaller, cheaper, and more readily available. This happens only sporadically in Battletech.
For example, only in the last ten years have the PTB in charge of Battletech added "primitive" versions of familiar equipment to the lists. The effect before this change was made was that a Large Laser produced in 2700 was the same weight, cost and effeciency as a Large Laser produced in 3025. Sure, the ER Large Laser improved on the normal weapon (ish), but the bog standard LL was no lighter, smaller, or cheaper than the 300 year old version. The Clans got a marginal improvement, and then proceeded to use the new versions in an almost nonexistent manner in most of the published material. Standard engines got no smaller or cheaper. XL engines were introduced, but again those seem to be completely different products with ridiculously higher costs. This is appropriate for a new technology, but the mature technologies seem to never improve.
Mekton has a fix for this. There is a section in Zeta Plus that allows for "Research Points" that can take a component or device and improve on it. For 20 RP, one can take an established piece of technology and make it up to 10% smaller, lighter, cheaper, or more efficient. For 100 RP, an Innovation is created. This can improve a characteristic of an invention up to 33%, or combine an Improvement with an Innovation. For example, a 10% increase in damage for a weapon would be a 20RP Improvement. Add this to a 60RP Innovation reducing the size of the weapon by 33% and another 60RP for combining the Improvement and Innovation and the net result is a weapon that's 1/3 smaller and 10% harder hitting for the same cost and mass as the original. Further research could reduce the cost further, or boost range, or... anything. It just takes time and research. 100RP constitutes an Invention, and that's something entirely new.
The reason this would be a bit cumbersome becomes quickly apparent. One would have to keep track of Improvements, Innovations and Inventions on literally every single item, since they don't apply to classes of item, but particular items. For example, if this system were applied to Battletech one could take a particular weapon, let's say a Medium Laser, and apply an Innovation to add a 10% range boost (+1 Hex, basically), and then two Innovations to increase the damage by 33% (+2 points) and combine this with the range bonus. One would then have a Medium Laser that did 7 points of damage at up to 10 hexes range. This would effectively add a new weapon to the weapons list. One would assume this weapon is only available to the faction who invented it, and only on 'Mechs created or refit since its inception. Complexity would jump upward very, very quickly. On the bright side, there would finally be a reason to select a Martell Medium Laser over an Aberdovey or ChisComp Medium Laser, as they could all potentially have different stats.
This is where the argument of flavor over playability comes into the discussion. Is it more valuable to your game to have every weapon be unique for flavor's sake, or for every Medium Laser to be identical to cut down on referencing stats during battles? Speed, or depth? What is more essential to the feel you want out of your campaign?
All that said, reading this over has given me some ideas I want to use. My MechWarrior campaign in the Royal Dragoon Guards has revamped some of the tech assumptions in 3038 to give some advanced techs to the Inner Sphere factions to add flavor to their forces. Kurita got some advanced PPC tech. Davion got some advanced autocannon tech. Liao got some ECM tech. Things like that. Using Mekton, I am beginning to cobble together ideas for breaking down the tech in Mekton Zeta Plus into categories and trees similar to the Inventions table in Space: 1889. This would allow a baseline tech level, then GMs could assign knowledge of certain advanced techs to factions and allow PCs to control the research efforts of their own factions to attempt to improve on what has come before. In a campaign where the GM is creating or controlling warring factions in the pattern of the Successor Houses in Battletech, this could allow each House to have its own particular technological feel and have that feel trickle down into the design of their combat units.
Of course, this suggests a bit of a metagame for the players that has shades of Master of Orion. A clever GM could add a lot of concepts from those PC games into the tabletop campaign. Espionage- can the PC faction steal new tech from other factions? Can other factions teal from the PCs? Economics - Is it enough to have the most technologically advanced mecha when your neighbor can throw five times as many of their less advanced mecha against you? Technological - should our scientists attempt to unlock the secrets of more damaging energy weapons, or spend their time inventing better armor?
This whole concept bears a lot more thought.