As a generalist design to put on the line, the base MDG-1A is still a passable machine in stock form. The designers cannot be faulted for their choices, considering the times. However, in the "modern" era of battletechnology, the somewhat endurable flaws are now glaring.
The main thing that hurts the baseline model is the unprotected missile bays. With the subpar armor for a seventy five tonner, this amounts to a cardinal sin. It was bad enough at the time of it's roll-out, considering who it was mainly designed to fight. Now, it's a serious issue in my book.
The options without radical overhaul? CASE the missile bays and add armor. Or, in the post-Jihad era, CASE II in each side torso. Sure you lose the Artemis FCS. But the kind of ECM heavy AOs you find in our games kinda makes the old Artemis, more or less, a situational tool. Then the One Alpha goes from "serviceable" to "good". That's just my opinion.
I can't fault the loadout. It's actually standard fare for a line generalist in it's weight class. Combined with the above average mobility for it's weight class (for the times), it can work. Just, as I said before, the ammo issue is a major black mark against it, when the armor protection is taken into account.
In my opinion, the -1B field modification was an answer to a non-existent problem. Compared to some of it's cousins introduced around the same time period, the -1A was fairly heat efficient IF the controlling player(s) didn't go apeshit with barrage fire. But still, any reduction to the heat curve is a good thing. And despite the fact that it loses the range in the main guns, it still makes a nice nimble missile boat for the fire lances.
The Rakshasa-2A? Same issue as the base variant. It's solid, with a (thankfully) standard minimum three ton magazine for the RAC. And it's even more dangerous up close. BUT, it still has a bad case of the "Walking Bomb Syndrome".
The -1Ar finally addresses these issues, while adding increased mission flexibility. This variant gets high marks on my scorecard. It's also fast replacing the stock MDG-1A as the "go-to" canon Rakshasa variant, in my playgroup, when generating forces. This version compliments the home refits of the older models nicely.
In a nutshell, overall, the Rakshasa was a decent heavy 'Mech that got better with time.