Indeed. Once I house ruled it, I found the Palladium system to be pretty fun and smooth. The rest of the game needs work though and there is no such thing as balance. In RIFTS you could have a party with one player playing a homeless guy alongside another player playing a demi-god.
And Mekton Zeta is pretty cool. I have never played it but I own all the books for it.
QFT.
I get into an ongoing argument with my girlfriend's sister, who is an avowed RIFTS fan. This girl has never played any other RPGs... but she asserts that RIFTS is better than any other RPG. Why? It's more fun, it has more options, and whatnot.
I tell her that the game has unbalanced combat rules, and that the classes are horribly unbalanced. Her response is "Well, the GM can fix all that."
Then she tells me how limited D&D is, because it only has ten or so basic classes. ("Even if you add all the books, there's only, like, thirty classes!")
It's an aneurysm, everytime I get into this argument.
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The unbalance between characters in RIFTS is well known, even if you just use the core book. I once played a game where we had a vagabond (an unskilled wanderer), a Wilderness Scout with uber physical skills, and a Glitter Boy (super mech boy!). Basically, the Wildnerness Scout got the group around, and the Glitter Boy killed anything that got in the way. And the Vagabond... he, uh.... I'm sure he did something. Cooked meals, did some laundry, stuff like that.
There are even classes that are very similar, with one having an obvious edge over the other. This can be seen in the "Rogue Scholar" and the "Rogue Scientist" classes - one is obviously just an improved version over the other. Really, the only thing that seperates the two is fluff - and when fluff and background are sort of built into the class, it can get kind of limiting.
***
Luckily, Robotech is much better than RIFTS in terms of class balance, because each character has access to each type of Mech. And mechs are the big part of the game. Plus, the game is much more balanced in terms of damage codes vs. M.D.C.
Just... don't use other rule books in your ROBOTECH game. It'll destroy things, fast.