In LLPSI Orberg scripsit hanc sententiam: ‘Post tanta negotia magis quam umquam otio fruor’
Now I know what this means but I’m not sure of the syntax: ‘magis’ is a comparative adverb: magnopere, magis, maxime.
So ‘magis’ qualifies ‘fruor’ - ‘I enjoy better’ - can’t think of a good English translation.
But what’s the purpose of quam? Does it indicate ‘as’ ? What’s its role in the sentence?
Hm, what are you doing with “quam umquam”?
Magis is a comparative adverb formed from magnus, so it is going to mean something like “more greatly”. It’s usually best translated simply as “more”.
In comparisons, quam means “than”. Pulchrior sum quam tū. The two things being compared are always in the same case. Eam magis quam vītam amō.
Another way of making a comparison is with the ablative case. Pulchrior tē sum. Eam magis vītā amō.
otio fruor
magis post tanta negotia
quam umquam
What is being compared are the adverbial expressions of time. The phrase “post tanta negotia” is the adverbial expression of time that is being compared to umquam:
I enjoy this leisure, otio fruor,
more now, at this time, post tanta negotia,
than at any other time before now, umquam.
Thanks. Laura I think you nailed it.
What’s fun here is the play between otium and negotium (nec-otium, non-leisure). That’s what is hard to capture in English, since our words “business” and “pleasure” don’t have that nifty etymological relationship that Latin has with otium and negotium. 
“After so many activities, more than ever I enjoy inactivity.”
“After so much that’s taxing, more than ever I enjoy relaxing.”
“After so much pressure, more than ever I enjoy leisure.”
“After so much that’s taxing, more than ever I enjoy relaxing.”
Mihi MAXIME placet!!!