At 8 tons a piece for the nukes, and given their huge reload cost you can save at least a point of MV/TR dropping those, or drop all missiles (the SWM-5's are 6 tons fully loaded) and fit another pair of pretty decent guns on that mech. (The vadel's VC-5s are a personal favorite of mine for close range mop up at only 2.5 tons for a lot of firepower, the Chimentero Heavy Phase cannons are also good for an energy weapon equivalent. Good weight reduction MAC-4's aren't bad for twice the range of VC-5s, or for range plus even heftier damage at higher weight RG-8's. The Roc has a good reduced weight RG-8 on it.) With that said, there's little to compare with the instantaneous firepower of missiles (especially if you set missile burst value to max from the combat menu), if you can afford to keep up with reloads.
And yeah, even if you can dodge most everything, things like LINE, BLAST, or SCATTER weapons will still almost always hit you. Luckily they split the damage randomly over the mech, but that still means you'll be happy to have at least some armor to soak up those kinds of hits.
For a close range optimized Savin without going through quite so many hoops:
Starting with the Gladius variant of the Savin available occasionally from high value Pro Duellist shops (for it's Highperformance engine +1/+1), and with relatively few internal changes (switched to chimentero sensor, Roc ECM, switched VC-5 for vadel VC-5, dropped battery from head and MAC-4 from chest) changed out the armor basically as above, no bothering with limbs other than the wings from a Gigas for good, low weight, space to put some overchargers in. Optionally, I believe one of the Blades of Crihna areofighters or hoverfighters has some wing armor.
For weapons, the Nova Scythe, a Mecha Blunderbuss (replace with any better Scatter weapon you get from theme mecha or some such, or possibly Blast weapons. Both have a large bonus chance to hit saving you XP spent into Gunnery when you want to be concentrating on Fighting), a pair of THROWN RETURNING weapons taken from the low cost Picaro, and to help you close the gap, Nightfall missiles from a Bargol on one leg, and a Smoke Launcher on the other. And a VC-5 from a vadel for INTERCEPT vs missiles.
Final stats:
MV/TR/SE: -1/-1/+5 max speed 277
*however* If you're going that heavily towards melee, the Pixie itself can be reworked to carry most of that gear (dropping probably the missiles and smoke launcher and a few other bits and bobs) and being a Class 5 is faster and more maneuverable.
But a more rounded approach with a melee backup like you seem to do is probably the saner way to go.
As for things to look out for salvage-wise besides the ones I've mentioned:
The Blades of Crihna heavy hover/areofighters have good computer programs that can be borrowed, although there are better computers on a couple of different mechs, the weapons I've mentioned are the main ones I make use of, but there's a few more that can be pretty good as well although I'm drawing a blank currently. PHS-8's (Phase Cannon, DC 8 Armorpiercing) are good for people with the Sniper talent, but I don't think there are any reduced weight variants. Very few special versions of the LAS-10 (Laser Cannon DC 10) as well, although it's also fairly nice. In GH1 with the reduced weight LAS-10's from the Harpy and some PHS-8's from somewhere (and no energy pool to drain) you were just about set.
You'll probably have to check out the MUGL specific corporate stores to find a Pixie to buy, incidentally.
Also for close-range fighters, I really recommend having some method of inflicting Haywire/Blind to keep people busy while you're closing the gap, and possibly some method of Overload status to get their MV lowered if they keep dodging you. Nothing worse than being down to your melee weapon on a space map and getting one swing every 10-20 movement rounds as you pass by each other and missing.
Hmm, and I went smaller arms/same class legs on the first Savin variant I did above. The Dao Deoji has some good Class 8 legs for an extra internal space to fit gear, and you can install limbs up to 1 size larger than the class/torso size of the mech you're working on. And the Bargol arms are fairly decent Class 8's as well, with the downside that they come with Integral energy weapons that can't be removed. Still, not a bad choice if you like the weapons they have. (Dao Deoji arms are Class 9, incidentally, they're have decent mass reduction, but at 2 size classes higher than the Savin you couldn't use them on a Savin. Although the Dao Deoji is also an excellent base frame to consider removing all unnecessary gear from and building up from. Even slower than the Savin, but capable of packing in/carrying even more amounts of firepower.)
In case you couldn't tell, I spend a lot of time comparing and contrasting different gear from the different mechs. Heh.