Linn lp 12 upgrade or new TT ? please help.

Had the exact same set up (with a Klyde cartridge) and like you was faced with the same dilemma. The thing with any Sondek is that you have to spend really serious money to get it up to current standards, only to realize that there still is a long way to go. As an example, the Hercules is a worthwhile upgrade (way better than the Nirvana IMO) but it is not in the same league as the Lingo, which itself is now way behind the latest Linn offerings. The same applies for any of their tonearms or suspensions. I appreciate the flexibility but you end up spending thousands on what is essentially a 40 year old design on steroids. Not to mention the notorious setting up/tuning out problems and the occasional suspect reliability problems. Bottom line: go for a newer design and marvel at the trouble free good sound it can offer. The Avid II is a great table (and you can still use your Akito) - a lightly used VPI is always a solid choice - while a Clearaudio or a Pro-ject are also solid bets.

Since you are going down the upgrade road, you should also seriously consider an upgrade in the power supply. If the lingo seems expensive, Origin Live make their own separate (external) power supply that also fits the Sondek. It comes in three different guises to suit different pockets; have not heard it myself but got some sterling feedback from other Linn users. If that does not fit the bill, do try the Herc upgrade. Trust me, sound wise, it is worth the outlay over the Nirvana.