Matt -
I have a 2006 Avalanche with a 150. Gets on plane very quick and tops out at around 61MPH. I agree with the previous posts that the 115HP will be too underpowered, look for 135 or higher. The other point is, I have Hydraulic steering which makes a world of difference. Regarding the boat sitting higher in the water, it does....the boat is really a cross-over between a true bass boat and multi-species. As far as being blown all over the place, I really haven't seen much difference from other 19 foot boats I have been in, fiber or aluminum. A trolling motor with 100lbs plus of thrust would be nice and I plan to buy one for next spring given I can now justify it given the original has given me 3 years of flawless performance and taken a beating on rocks and stumps. Keep in mind I have had the boat in rivers with pretty strong current and the boat and trolling motor did very well. I just don't like the fact when the trolling motor is set to the highest level of "5" and when you press the foot pedal to start the motor all the current hits at once where the boat and trolling motor can jerk and if you are not ready for it you could loose your balance and possibly fall over. Hasn't happen to me but I have lost balance.... From what I understand the newer digital trolling motors ramp slowly with the current to avoid the jerking.... Keep a strong footing on the trolling motor foot pedal and you will be fine. As far as the hull issues, the first year and early 2003's had issues with the welds on the transom, be careful....
Stability, I am 250 and with others on the boat you will be very stable given the beam is 8 feet. I have had four male adults on board with no problems. I love this boat, great ride, have had it on Lake Winnipesauke here in NH in the broads during 3 to 4 foot swells and the boat handle great. I would not suggest doing this by the way...FYI - this was the only time I ever got water in the hull where the bilge kicked in. I have the electric one that comes with the boat as well as an auto bilge.
Other than some paint issues with the hull, I have not had one problem with the boat. The paint issue was due to poor primer application and taken care of by the dealer and Tracker. Great support and service from both....
FYI - I put an 8 inch Keelshield on when I bought in 2006 and it has held up great. No keel scratches other than where the boat has hit the bunks when loading.
The boat is not longer be made due to it's high cost to manufacture so it may be difficult to get parts down the road. The way I look at it is, it's just like any other boat which stops production.
Good luck, make sure to do your research, take one for a test run and have a person who knows boats take a look at it.... Like I said I love this boat and have no plans to go fiber given the ramps, or there lack of here in the Northeast are terrible and having a fiber boat the keel will get destroyed from the rocks and gravel every time I load and unload passengers.
Dan