Klipsch Forte ii too bright, or is it my room ?

1. Every speaker I have ever owned has benefited from room treatment. If what you're describing is accurate, (room) you won't be totally happy with any speaker until you take care of the room.
2. Those old Pioneers Receivers are grainy and miserable sounding... get rid of it!
3. Klipsch speakers done right, in the right room can be transforming! You might need to spend some time and money with crossovers, a little damping, tube amps, interconnects, etc. 

Ozzy62 maybe I should have simplified it for you.most people don’t have 20+ years into mods throughout .
in the vast majority of speakers the Stock Xover is a liability ,
or weak link. The room for sure can be problematic .
not seeing the layout ,and damping,or lack of is hard to say what is needed 

Free: Aim the speakers straight ahead with no toe in.  This will decrease the perceived treble at your listening position, assuming that you sit centered between the speakers.

Free: Position the speakers at the best distance from the front wall behind them to reinforce the bass.  I have my GoldenEar speakers at 19.5 inches from the front wall, but your speakers should probably be something like five or six inches from the wall.

Free: Position your listening chair at the best distance from the back wall to reinforce the bass.  I have my chair positioned so that my ears are 20 inches from the back wall (and I have a curtain and absorption panels behind me).  Experiment to find what works best for your room and speakers.

Low cost: Position a large rug on the floor directly in front the speakers.

Low cost: Place curtains over the windows.

Low cost: Attach a large blanket or curtain on the front wall centered behind the speakers and another one on the wall directly behind you.

As funds permit: Purchase absorption panels and place a few of them on the wall behind the speakers, more on the wall behind you, and on the first reflection points on the sidewalls.  You can use two inch thick acoustic foam panels for this because you only need to attenuate the treble and maybe the upper midrange.  You don't need to cover the entire walls with absorption panels.

It could be that you find that none of this is enough, but it will help and it costs very little.

I had a new Pioneer receiver in 1980 and would rock out with Led Zeppelin way back then.  I did nothing to treat the room and it sounded great.  But as funds permit, your old receiver needs to be replaced with a new warm sounding amp/receiver.  There are some warm amps/receivers that cost less than $800 new.  Some YouTube channels to help find one include the Audiophiliac, Jay soulsik, and Zero Fidelity.  All of them review budget gear that sounds great.  Jay's YouTube channel also has a video about how he treated his room using items from a very low cost vendor.

You should know that many tube amps run hot and will heat up your entire room.  So do most class A solid state amps.  One option would be to purchase a class AB receiver that sounds warm.  Most class AB amps/receivers run cool.

Let us know how your efforts progress.

Zero Fidelity has a review of the Sony STR-DH190 Stereo Receiver.  Price: $170.  He says it is neutral and does not have tipped up treble.  And he said it plays well with Klipsch speakers.  It has tone controls so that you can reduce the treble if needed.  It has Bluetooth but no digital connections, and so if you want to play music from a connected computer with cables you would need an external DAC.

The price is so low that you could get it now, keep it for a few years, and then get something better later.

He also compares it to a $500 integrated amp.

Another consideration for receivers and amps is that the high sensitivity Forte II does not need many watts to play loudly.  That provides more amp/receiver options and can help keep the cost down.

To help make you feel great about your Klipsch speakers, check out the YouTube video by Andrew Robinson about why he loves Klipsch speakers.  Search YouTube for "WHY PERFECTION DOESN'T MATTER - La Scala Review"

Andrew Robinson said that one of the amps/receivers that sounds the best with his Klipsch speakers is a Pioneer that he had restored.  So, that could be an option for your receiver.