Sadly, the small 3.750" bore makes it near impossible to boost CCP up in the 185-190psi range which is a good target for a mild street motor. Since you don't want to pull the heads, you will need a cam with an early intake close; JMHO but the best choice for a cam only upgrade to a Stage I TC88 would be the S&S 509. I would also suggest that you consider installing a set of 1.7 ratio rocker arms to take advantage of the higher lift allowed by the '05 beehive springs.
I am a big proponent of gear driven cams; however, I have to say that with the new hydraulic setup which you have already installed; the cost benefit of gears over the hydraulic setup just isn't there and the chain set up will tolerate crank run out > .003". Conversion to gear driven cams is a $500 conversion. The money would be better spent on boring your cylinders to 95"/98", fitted to a set of CP or Wiseco pistons with 6cc dome; this will eat up that $500. Go on the hunt for a set of '06 or later heads; I have seen them go for $150-$200; much improved over the '05 heads which were the worst.
Have you had any oil consumption issues? Many '05 owners have had the guide seals replaced under warranty for excessive oil consumption. Have the '06 heads cleaned up, new guide seals and a multi angle (SERDI) valve job done and put the top end together with a .030" MLS head gasket. At this point, you have your choice of several cam sets; Andrews 48, Cylerama 575, TMan 555 Torkster, Woods 222, SE204 to mention a few. (The SE211 has an intake close @ 45*, way too late for strong low/midrange performance) I would go for the Cycle Rama 575 or the Andrews 48, in that order, but any of the aforementioned cams will do the job and deliver strong low and midrange performance up to 4500-5000rpms, peaking between 3000-3500 rpms. 100/110 numbers easily achieved with more displacement.
Of course, fuel management and a proper dyno tune are necessary to optimize the performance in either case; cam only or bigge bore and cams; I know, mo money.
Anyway, probably more information than you wanted/needed but you have some options.