Welcome aboard and I hope we can help. DW and I spend more of our time in the Hill Country of Texas and I'm not an expert on East Central area. Three State Parks come to mind though. Tyler SP is very nice and has a small lake that's great for 'yaks. Have camped there 2-3 times and would return any time.
TPWD: Tyler State Park
Cooper Lake SP (South Sulpher Unit) is very nice and a larger park on a larger lake. We haven't camped there but did take a look at it a few years ago. It's on our "to camp" list.
TPWD: Cooper Lake State Park
Purtis Creek SP is very nice for camping. It has a small lake but as of my last check, boating is limited to a total of 50 on the lake at any given time and there is a daily fee to put your boat in the water. Not sure what the reasoning is for this but it could put a crimp in your plans. I understand that this little lake has been known to produce some pretty nice bass.
TPWD: Purtis Creek State Park
BTW: DW and I also have a pair of 'yaks we like to get out when we can. We have 2 "Rides" by Wilderness Systems that we have been very pleased with. Had hoped to have them out the last couple of days but weather and prior commitments conspired to make that impossible

. Oh, well. There's always next week

.
That's about all I can think of at the moment. Feel free to post any further questions and either I or another of our members will do our best to answer. Until then and always,
Happy Camping!
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Turn Key, DW & Tilly, The Camping Boston Terrier
'03 Chevy 2500HD, 4X4, X-Cab, Long Bed
'04 K-Z "Durango", 275RK ("Sunday Haus II")
Twin Kayaks, "The Ride" by Wilderness Systems
North Central Texas, Where The West Begins!