Your comparing apples to oranges its not a vs type thing…
Think or swim is a broker that gives you access to multiple exchanges. You can trade options, futures, forex, stocks ETF’s etc…
Nadex is not a broker it is an actual exchange. Instead of trading through a broker you are trading directly on an exchange.
Options may increase or decrease your probability of success depends on what your doing
You do not have to combine stocks with options
You do not increase your probability by reducing your cost basis you just limit your risk (potentially as there are option strategies with uncapped risk)
An option is not called a coupon. A option is what is included in a contract you get x options per contract. A coupon is a treasury term for interest payments.
The price you are buying or selling (not necessarily the value as there is intrinsic value (real value if expired immediately ITM) and extrinsic value (time and implied volatility value) if it expired immediately ITM. You may make or lose either depending on on of over 100 option strategies one can use to combine options.
On all option style derivatives - nadex or call or put options on TOS the value is derived from the underlying, the implied volatility, the relation of the instrument to the strike, and the amount of time left until expiration.
Nadex binaries are in essence the delta of a call option with the same strike and expiration time as a call option.
Nadex spreads use a black shcole model like a call or put option on TOS (ie check US 500 spreads and calls with same ceiling or puts with same floor as spreads (5 spread to 1 ES option) and you will see they have the same risk. Nadex prices spreads in ie risk + the strike (where as a call is just priced as the risk/50 on ES.
A faster way to put it - nadex is options for day traders as your not paying for days weeks of premium you dont need, maximizing the delta to 1 fast and getting killer gamma. So if hedging, or straddling, or doing neutral plays, or directional in all conditions you get more bang for your buck and you can risk in smaller amounts meaning you can do small or larger risk but better control the % at risk versus having to do 50 or 100 or whatever # of options at a time like on exchange traded options listed on TOS and many other brokers.
I love TOS but again this is apples and oranges.