675 New To Me 2010 Street Triple R

That is a nice clean look example you have there. I too like the under seat exhaust tailpipe look and being that the bike was designed to use such, I wonder why people would change it unless it's just to save even more weight on an already light machine.
The most popular slip ons over here in Germany seem to be the Arrows which mine has although the original cans might actually be quietest and cheapest if that's important to you.

 

Hi Eric. Your STR looks to be in great shape and in a really nice colour combination.

On clutch pull - if you have the "shorty" adjustable levers, see if you can pick up a standard clutch lever cheap and try it to see if that makes a difference. I put Triumph's short adjustables on my ST675 and found it VERY uncomfortable to pull the clutch and my wife tried them on hers and said they were impossible! I'm not suggesting you have girlie hands, by the way! You just might find that the short lever is making clutch pull that bit harder - it's usually fairly light on the ST. If a standard length lever doesn't have any effect to change the weight of the pull, then a new cable is the next obvious choice.

On exhausts/silencers (mufflers). From your posted picture it looks like you're going to need the link pipe that kicks the exhaust up and towards the seat - you might even need more than that if a previous owner has deleted the cat to get more noise! It should be possible to get a set of headers/pipes from a parted out bike at a reasonable cost.

I'm with you all the way on the Street (and Speed) Triple looking SO much better with high level, underseat cans but it IS always a matter of personal taste and preference. It's inarguable that a low level pipe and silencer will reduce weight - and from the best of places, i.e. high on the bike - but the original Street Triple was, for me, a bit of a groundbreaker with twin underseat silencers giving a lovely, styled and balanced view from side and rear. I was close to buying a set of Danmoto titanium silencers recently just to keep as a spare set since I'm not ever likely to sell the bike and exhausts don't last forever. The original ad was on the US ebay site and the pipes were incredibly cheap but I've just looked and the listing shows them as sold out.

https://www.ebay.com/p/1244204952

I've just checked on Danmoto's website and they are still showing as listed at half price for the carbon wrapped version - which would match your bike a treat!

https://www.dan-moto.com/index.php?main_page=product_info&cPath=1_74_84&products_id=333

At $132 for the full set (excluding baffles, which, I suspect, you would definitely need!!) it might be a no-brainer! You'd still need the cat-back pipe, though but worth the wait for a part to come up on ebay! I think you'd get a chunk of that back by selling the "lowboy" - they seem to be in vogue and in high demand! As Danmoto are in Reno it would even make a nice trip from Sacramento.

Last thing, you might need to check that the rearsets you've got on there won't interfere with any mounting brackest for the exhaust - shouldn't, but worth double checking. Oh, and we need a picture once you've fitted whatever silencers you do eventually choose!