Thankyou for the thoughtful response on all fronts.I can say this. Having more current for the Timeless doesn't necessarily make them sound "better" but will drive them to their full potential will make them drive to what was intended. Whether you like that sound better or not is subjective. So basically, driving them to their full potential will require some current to do.
Running them directly from a phone or PC/MAC will most likely not do this. But I would argue that some people will find this sound pleasing to them. The bass will be boomier (less textured), and the sound becomes more relaxed, though you most likely WILL hear those sibilant issues talked about earlier in the treble area more often. There will be a certain amount of "grainy(ness)" introduced to the overall sound when not driven properly. Your ears may or may not hear this so YMMV.
You may or may not. I personally don't find the Timeless and Sundara as similar as other folks have mentioned other than that planar thing (tight fast transients, clarity). But you can pretty much get that generic similarity from any planar of quality. That being said they are best driven with more current, but you may find the sound pleasing straight out of your Macbook, or Phone (see above). With less current, the bass is boomier, mids are a bit thinner and recessed (the V signature more pronounced), and the highs are less resolving making them sometimes a bit harsh (not often though). Take that with a grain of salt as those changes are more subtle than I am making them sound.
Overall if you like the sound signature that the Timeless are, then you will probably love them because they ARE very good for the price. The same will go for the Sundara. I would suggest that you try and find a way to audition the Sundara before you commit to them. I landed on the Deva because they are similar to the Sundara in sound but are also capable of hi-res bluetooth with just a cable swap.
The Timeless are worth the $200 asking price for sure. Keep in mind these are a planar but are tuned more like a consumer IEM rather than audiophile tuning. Nothing wrong with either, but they are different targets in their tuning. These are not neutral and aren't meant for critical/analytical listening, but on the other hand, they have a super fun tuning. They are very pleasing listen (and non-fatiguing overall unless overexaggerated bass is fatiguing to your ears)!
As for EQ, I can't answer that question because I am not in the Apple ecosystem (windows/android for me). But doing a google search will most likely help you out there. Personally Peace for windows is a super powerful (but high learning curve) EQ. This can't be used on Mac though because it lacks the Equalizer APO needed to run it. For android I find Neutron player the best in the business (meant for audiophiles). It is bit-perfect (bypassing the android limitations), and when needed, has one of the best EQ apps that I have seen.
One of the things I like about the latest MacBook Pro is the headphone Jack. It supples 1.25v up to 150ohms and has support of 3v for 150 to 1k ohm. I haven’t compared but others have claimed their chord mojo was a fairly minor improvement over direct input which is quite impressive really.
Cheers.